blob: 92a5e7629fb604058db213fe30909ae0dd342787 [file] [log] [blame]
#[cfg(feature = "yaml")]
use std::collections::BTreeMap;
use std::rc::Rc;
use std::ffi::{OsStr, OsString};
#[cfg(target_os = "windows")]
use osstringext::OsStrExt3;
#[cfg(not(target_os = "windows"))]
use std::os::unix::ffi::OsStrExt;
use std::env;
#[cfg(feature = "yaml")]
use yaml_rust::Yaml;
use map::VecMap;
use usage_parser::UsageParser;
use args::settings::ArgSettings;
use args::arg_builder::{Base, Switched, Valued};
/// The abstract representation of a command line argument. Used to set all the options and
/// relationships that define a valid argument for the program.
///
/// There are two methods for constructing [`Arg`]s, using the builder pattern and setting options
/// manually, or using a usage string which is far less verbose but has fewer options. You can also
/// use a combination of the two methods to achieve the best of both worlds.
///
/// # Examples
///
/// ```rust
/// # use clap::Arg;
/// // Using the traditional builder pattern and setting each option manually
/// let cfg = Arg::with_name("config")
/// .short("c")
/// .long("config")
/// .takes_value(true)
/// .value_name("FILE")
/// .help("Provides a config file to myprog");
/// // Using a usage string (setting a similar argument to the one above)
/// let input = Arg::from_usage("-i, --input=[FILE] 'Provides an input file to the program'");
/// ```
/// [`Arg`]: ./struct.Arg.html
#[allow(missing_debug_implementations)]
#[derive(Default, Clone)]
pub struct Arg<'a, 'b>
where
'a: 'b,
{
#[doc(hidden)] pub b: Base<'a, 'b>,
#[doc(hidden)] pub s: Switched<'b>,
#[doc(hidden)] pub v: Valued<'a, 'b>,
#[doc(hidden)] pub index: Option<u64>,
#[doc(hidden)] pub r_ifs: Option<Vec<(&'a str, &'b str)>>,
}
impl<'a, 'b> Arg<'a, 'b> {
/// Creates a new instance of [`Arg`] using a unique string name. The name will be used to get
/// information about whether or not the argument was used at runtime, get values, set
/// relationships with other args, etc..
///
/// **NOTE:** In the case of arguments that take values (i.e. [`Arg::takes_value(true)`])
/// and positional arguments (i.e. those without a preceding `-` or `--`) the name will also
/// be displayed when the user prints the usage/help information of the program.
///
/// # Examples
///
/// ```rust
/// # use clap::{App, Arg};
/// Arg::with_name("config")
/// # ;
/// ```
/// [`Arg::takes_value(true)`]: ./struct.Arg.html#method.takes_value
/// [`Arg`]: ./struct.Arg.html
pub fn with_name(n: &'a str) -> Self {
Arg {
b: Base::new(n),
..Default::default()
}
}
/// Creates a new instance of [`Arg`] from a .yml (YAML) file.
///
/// # Examples
///
/// ```ignore
/// # #[macro_use]
/// # extern crate clap;
/// # use clap::Arg;
/// # fn main() {
/// let yml = load_yaml!("arg.yml");
/// let arg = Arg::from_yaml(yml);
/// # }
/// ```
/// [`Arg`]: ./struct.Arg.html
#[cfg(feature = "yaml")]
pub fn from_yaml(y: &BTreeMap<Yaml, Yaml>) -> Arg {
// We WANT this to panic on error...so expect() is good.
let name_yml = y.keys().nth(0).unwrap();
let name_str = name_yml.as_str().unwrap();
let mut a = Arg::with_name(name_str);
let arg_settings = y.get(name_yml).unwrap().as_hash().unwrap();
for (k, v) in arg_settings.iter() {
a = match k.as_str().unwrap() {
"short" => yaml_to_str!(a, v, short),
"long" => yaml_to_str!(a, v, long),
"aliases" => yaml_vec_or_str!(v, a, alias),
"help" => yaml_to_str!(a, v, help),
"long_help" => yaml_to_str!(a, v, long_help),
"required" => yaml_to_bool!(a, v, required),
"required_if" => yaml_tuple2!(a, v, required_if),
"required_ifs" => yaml_tuple2!(a, v, required_if),
"takes_value" => yaml_to_bool!(a, v, takes_value),
"index" => yaml_to_u64!(a, v, index),
"global" => yaml_to_bool!(a, v, global),
"multiple" => yaml_to_bool!(a, v, multiple),
"hidden" => yaml_to_bool!(a, v, hidden),
"next_line_help" => yaml_to_bool!(a, v, next_line_help),
"empty_values" => yaml_to_bool!(a, v, empty_values),
"group" => yaml_to_str!(a, v, group),
"number_of_values" => yaml_to_u64!(a, v, number_of_values),
"max_values" => yaml_to_u64!(a, v, max_values),
"min_values" => yaml_to_u64!(a, v, min_values),
"value_name" => yaml_to_str!(a, v, value_name),
"use_delimiter" => yaml_to_bool!(a, v, use_delimiter),
"allow_hyphen_values" => yaml_to_bool!(a, v, allow_hyphen_values),
"require_delimiter" => yaml_to_bool!(a, v, require_delimiter),
"value_delimiter" => yaml_to_str!(a, v, value_delimiter),
"required_unless" => yaml_to_str!(a, v, required_unless),
"display_order" => yaml_to_usize!(a, v, display_order),
"default_value" => yaml_to_str!(a, v, default_value),
"default_value_if" => yaml_tuple3!(a, v, default_value_if),
"default_value_ifs" => yaml_tuple3!(a, v, default_value_if),
"env" => yaml_to_str!(a, v, env),
"value_names" => yaml_vec_or_str!(v, a, value_name),
"groups" => yaml_vec_or_str!(v, a, group),
"requires" => yaml_vec_or_str!(v, a, requires),
"requires_if" => yaml_tuple2!(a, v, requires_if),
"requires_ifs" => yaml_tuple2!(a, v, requires_if),
"conflicts_with" => yaml_vec_or_str!(v, a, conflicts_with),
"overrides_with" => yaml_vec_or_str!(v, a, overrides_with),
"possible_values" => yaml_vec_or_str!(v, a, possible_value),
"required_unless_one" => yaml_vec_or_str!(v, a, required_unless),
"required_unless_all" => {
a = yaml_vec_or_str!(v, a, required_unless);
a.setb(ArgSettings::RequiredUnlessAll);
a
}
s => panic!(
"Unknown Arg setting '{}' in YAML file for arg '{}'",
s,
name_str
),
}
}
a
}
/// Creates a new instance of [`Arg`] from a usage string. Allows creation of basic settings
/// for the [`Arg`]. The syntax is flexible, but there are some rules to follow.
///
/// **NOTE**: Not all settings may be set using the usage string method. Some properties are
/// only available via the builder pattern.
///
/// **NOTE**: Only ASCII values are officially supported in [`Arg::from_usage`] strings. Some
/// UTF-8 codepoints may work just fine, but this is not guaranteed.
///
/// # Syntax
///
/// Usage strings typically following the form:
///
/// ```notrust
/// [explicit name] [short] [long] [value names] [help string]
/// ```
///
/// This is not a hard rule as the attributes can appear in other orders. There are also
/// several additional sigils which denote additional settings. Below are the details of each
/// portion of the string.
///
/// ### Explicit Name
///
/// This is an optional field, if it's omitted the argument will use one of the additional
/// fields as the name using the following priority order:
///
/// * Explicit Name (This always takes precedence when present)
/// * Long
/// * Short
/// * Value Name
///
/// `clap` determines explicit names as the first string of characters between either `[]` or
/// `<>` where `[]` has the dual notation of meaning the argument is optional, and `<>` meaning
/// the argument is required.
///
/// Explicit names may be followed by:
/// * The multiple denotation `...`
///
/// Example explicit names as follows (`ename` for an optional argument, and `rname` for a
/// required argument):
///
/// ```notrust
/// [ename] -s, --long 'some flag'
/// <rname> -r, --longer 'some other flag'
/// ```
///
/// ### Short
///
/// This is set by placing a single character after a leading `-`.
///
/// Shorts may be followed by
/// * The multiple denotation `...`
/// * An optional comma `,` which is cosmetic only
/// * Value notation
///
/// Example shorts are as follows (`-s`, and `-r`):
///
/// ```notrust
/// -s, --long 'some flag'
/// <rname> -r [val], --longer 'some option'
/// ```
///
/// ### Long
///
/// This is set by placing a word (no spaces) after a leading `--`.
///
/// Shorts may be followed by
/// * The multiple denotation `...`
/// * Value notation
///
/// Example longs are as follows (`--some`, and `--rapid`):
///
/// ```notrust
/// -s, --some 'some flag'
/// --rapid=[FILE] 'some option'
/// ```
///
/// ### Values (Value Notation)
///
/// This is set by placing a word(s) between `[]` or `<>` optionally after `=` (although this
/// is cosmetic only and does not affect functionality). If an explicit name has **not** been
/// set, using `<>` will denote a required argument, and `[]` will denote an optional argument
///
/// Values may be followed by
/// * The multiple denotation `...`
/// * More Value notation
///
/// More than one value will also implicitly set the arguments number of values, i.e. having
/// two values, `--option [val1] [val2]` specifies that in order for option to be satisified it
/// must receive exactly two values
///
/// Example values are as follows (`FILE`, and `SPEED`):
///
/// ```notrust
/// -s, --some [FILE] 'some option'
/// --rapid=<SPEED>... 'some required multiple option'
/// ```
///
/// ### Help String
///
/// The help string is denoted between a pair of single quotes `''` and may contain any
/// characters.
///
/// Example help strings are as follows:
///
/// ```notrust
/// -s, --some [FILE] 'some option'
/// --rapid=<SPEED>... 'some required multiple option'
/// ```
///
/// ### Additional Sigils
///
/// Multiple notation `...` (three consecutive dots/periods) specifies that this argument may
/// be used multiple times. Do not confuse multiple occurrences (`...`) with multiple values.
/// `--option val1 val2` is a single occurrence with multiple values. `--flag --flag` is
/// multiple occurrences (and then you can obviously have instances of both as well)
///
/// # Examples
///
/// ```rust
/// # use clap::{App, Arg};
/// App::new("prog")
/// .args(&[
/// Arg::from_usage("--config <FILE> 'a required file for the configuration and no short'"),
/// Arg::from_usage("-d, --debug... 'turns on debugging information and allows multiples'"),
/// Arg::from_usage("[input] 'an optional input file to use'")
/// ])
/// # ;
/// ```
/// [`Arg`]: ./struct.Arg.html
/// [`Arg::from_usage`]: ./struct.Arg.html#method.from_usage
pub fn from_usage(u: &'a str) -> Self {
let parser = UsageParser::from_usage(u);
parser.parse()
}
/// Sets the short version of the argument without the preceding `-`.
///
/// By default `clap` automatically assigns `V` and `h` to the auto-generated `version` and
/// `help` arguments respectively. You may use the uppercase `V` or lowercase `h` for your own
/// arguments, in which case `clap` simply will not assign those to the auto-generated
/// `version` or `help` arguments.
///
/// **NOTE:** Any leading `-` characters will be stripped, and only the first
/// non `-` character will be used as the [`short`] version
///
/// # Examples
///
/// To set [`short`] use a single valid UTF-8 code point. If you supply a leading `-` such as
/// `-c`, the `-` will be stripped.
///
/// ```rust
/// # use clap::{App, Arg};
/// Arg::with_name("config")
/// .short("c")
/// # ;
/// ```
///
/// Setting [`short`] allows using the argument via a single hyphen (`-`) such as `-c`
///
/// ```rust
/// # use clap::{App, Arg};
/// let m = App::new("prog")
/// .arg(Arg::with_name("config")
/// .short("c"))
/// .get_matches_from(vec![
/// "prog", "-c"
/// ]);
///
/// assert!(m.is_present("config"));
/// ```
/// [`short`]: ./struct.Arg.html#method.short
pub fn short<S: AsRef<str>>(mut self, s: S) -> Self {
self.s.short = s.as_ref().trim_left_matches(|c| c == '-').chars().nth(0);
self
}
/// Sets the long version of the argument without the preceding `--`.
///
/// By default `clap` automatically assigns `version` and `help` to the auto-generated
/// `version` and `help` arguments respectively. You may use the word `version` or `help` for
/// the long form of your own arguments, in which case `clap` simply will not assign those to
/// the auto-generated `version` or `help` arguments.
///
/// **NOTE:** Any leading `-` characters will be stripped
///
/// # Examples
///
/// To set `long` use a word containing valid UTF-8 codepoints. If you supply a double leading
/// `--` such as `--config` they will be stripped. Hyphens in the middle of the word, however,
/// will *not* be stripped (i.e. `config-file` is allowed)
///
/// ```rust
/// # use clap::{App, Arg};
/// Arg::with_name("cfg")
/// .long("config")
/// # ;
/// ```
///
/// Setting `long` allows using the argument via a double hyphen (`--`) such as `--config`
///
/// ```rust
/// # use clap::{App, Arg};
/// let m = App::new("prog")
/// .arg(Arg::with_name("cfg")
/// .long("config"))
/// .get_matches_from(vec![
/// "prog", "--config"
/// ]);
///
/// assert!(m.is_present("cfg"));
/// ```
pub fn long(mut self, l: &'b str) -> Self {
self.s.long = Some(l.trim_left_matches(|c| c == '-'));
self
}
/// Allows adding a [`Arg`] alias, which function as "hidden" arguments that
/// automatically dispatch as if this argument was used. This is more efficient, and easier
/// than creating multiple hidden arguments as one only needs to check for the existence of
/// this command, and not all variants.
///
/// # Examples
///
/// ```rust
/// # use clap::{App, Arg};
/// let m = App::new("prog")
/// .arg(Arg::with_name("test")
/// .long("test")
/// .alias("alias")
/// .takes_value(true))
/// .get_matches_from(vec![
/// "prog", "--alias", "cool"
/// ]);
/// assert!(m.is_present("test"));
/// assert_eq!(m.value_of("test"), Some("cool"));
/// ```
/// [`Arg`]: ./struct.Arg.html
pub fn alias<S: Into<&'b str>>(mut self, name: S) -> Self {
if let Some(ref mut als) = self.s.aliases {
als.push((name.into(), false));
} else {
self.s.aliases = Some(vec![(name.into(), false)]);
}
self
}
/// Allows adding [`Arg`] aliases, which function as "hidden" arguments that
/// automatically dispatch as if this argument was used. This is more efficient, and easier
/// than creating multiple hidden subcommands as one only needs to check for the existence of
/// this command, and not all variants.
///
/// # Examples
///
/// ```rust
/// # use clap::{App, Arg};
/// let m = App::new("prog")
/// .arg(Arg::with_name("test")
/// .long("test")
/// .aliases(&["do-stuff", "do-tests", "tests"])
/// .help("the file to add")
/// .required(false))
/// .get_matches_from(vec![
/// "prog", "--do-tests"
/// ]);
/// assert!(m.is_present("test"));
/// ```
/// [`Arg`]: ./struct.Arg.html
pub fn aliases(mut self, names: &[&'b str]) -> Self {
if let Some(ref mut als) = self.s.aliases {
for n in names {
als.push((n, false));
}
} else {
self.s.aliases = Some(names.iter().map(|n| (*n, false)).collect::<Vec<_>>());
}
self
}
/// Allows adding a [`Arg`] alias that functions exactly like those defined with
/// [`Arg::alias`], except that they are visible inside the help message.
///
/// # Examples
///
/// ```rust
/// # use clap::{App, Arg};
/// let m = App::new("prog")
/// .arg(Arg::with_name("test")
/// .visible_alias("something-awesome")
/// .long("test")
/// .takes_value(true))
/// .get_matches_from(vec![
/// "prog", "--something-awesome", "coffee"
/// ]);
/// assert!(m.is_present("test"));
/// assert_eq!(m.value_of("test"), Some("coffee"));
/// ```
/// [`Arg`]: ./struct.Arg.html
/// [`App::alias`]: ./struct.Arg.html#method.alias
pub fn visible_alias<S: Into<&'b str>>(mut self, name: S) -> Self {
if let Some(ref mut als) = self.s.aliases {
als.push((name.into(), true));
} else {
self.s.aliases = Some(vec![(name.into(), true)]);
}
self
}
/// Allows adding multiple [`Arg`] aliases that functions exactly like those defined
/// with [`Arg::aliases`], except that they are visible inside the help message.
///
/// # Examples
///
/// ```rust
/// # use clap::{App, Arg};
/// let m = App::new("prog")
/// .arg(Arg::with_name("test")
/// .long("test")
/// .visible_aliases(&["something", "awesome", "cool"]))
/// .get_matches_from(vec![
/// "prog", "--awesome"
/// ]);
/// assert!(m.is_present("test"));
/// ```
/// [`Arg`]: ./struct.Arg.html
/// [`App::aliases`]: ./struct.Arg.html#method.aliases
pub fn visible_aliases(mut self, names: &[&'b str]) -> Self {
if let Some(ref mut als) = self.s.aliases {
for n in names {
als.push((n, true));
}
} else {
self.s.aliases = Some(names.iter().map(|n| (*n, true)).collect::<Vec<_>>());
}
self
}
/// Sets the short help text of the argument that will be displayed to the user when they print
/// the help information with `-h`. Typically, this is a short (one line) description of the
/// arg.
///
/// **NOTE:** If only `Arg::help` is provided, and not [`Arg::long_help`] but the user requests
/// `--help` clap will still display the contents of `help` appropriately
///
/// **NOTE:** Only `Arg::help` is used in completion script generation in order to be concise
///
/// # Examples
///
/// Any valid UTF-8 is allowed in the help text. The one exception is when one wishes to
/// include a newline in the help text and have the following text be properly aligned with all
/// the other help text.
///
/// ```rust
/// # use clap::{App, Arg};
/// Arg::with_name("config")
/// .help("The config file used by the myprog")
/// # ;
/// ```
///
/// Setting `help` displays a short message to the side of the argument when the user passes
/// `-h` or `--help` (by default).
///
/// ```rust
/// # use clap::{App, Arg};
/// let m = App::new("prog")
/// .arg(Arg::with_name("cfg")
/// .long("config")
/// .help("Some help text describing the --config arg"))
/// .get_matches_from(vec![
/// "prog", "--help"
/// ]);
/// ```
///
/// The above example displays
///
/// ```notrust
/// helptest
///
/// USAGE:
/// helptest [FLAGS]
///
/// FLAGS:
/// --config Some help text describing the --config arg
/// -h, --help Prints help information
/// -V, --version Prints version information
/// ```
/// [`Arg::long_help`]: ./struct.Arg.html#method.long_help
pub fn help(mut self, h: &'b str) -> Self {
self.b.help = Some(h);
self
}
/// Sets the long help text of the argument that will be displayed to the user when they print
/// the help information with `--help`. Typically this a more detailed (multi-line) message
/// that describes the arg.
///
/// **NOTE:** If only `long_help` is provided, and not [`Arg::help`] but the user requests `-h`
/// clap will still display the contents of `long_help` appropriately
///
/// **NOTE:** Only [`Arg::help`] is used in completion script generation in order to be concise
///
/// # Examples
///
/// Any valid UTF-8 is allowed in the help text. The one exception is when one wishes to
/// include a newline in the help text and have the following text be properly aligned with all
/// the other help text.
///
/// ```rust
/// # use clap::{App, Arg};
/// Arg::with_name("config")
/// .long_help(
/// "The config file used by the myprog must be in JSON format
/// with only valid keys and may not contain other nonsense
/// that cannot be read by this program. Obviously I'm going on
/// and on, so I'll stop now.")
/// # ;
/// ```
///
/// Setting `help` displays a short message to the side of the argument when the user passes
/// `-h` or `--help` (by default).
///
/// ```rust
/// # use clap::{App, Arg};
/// let m = App::new("prog")
/// .arg(Arg::with_name("cfg")
/// .long("config")
/// .long_help(
/// "The config file used by the myprog must be in JSON format
/// with only valid keys and may not contain other nonsense
/// that cannot be read by this program. Obviously I'm going on
/// and on, so I'll stop now."))
/// .get_matches_from(vec![
/// "prog", "--help"
/// ]);
/// ```
///
/// The above example displays
///
/// ```notrust
/// helptest
///
/// USAGE:
/// helptest [FLAGS]
///
/// FLAGS:
/// --config
/// The config file used by the myprog must be in JSON format
/// with only valid keys and may not contain other nonsense
/// that cannot be read by this program. Obviously I'm going on
/// and on, so I'll stop now.
///
/// -h, --help
/// Prints help information
///
/// -V, --version
/// Prints version information
/// ```
/// [`Arg::help`]: ./struct.Arg.html#method.help
pub fn long_help(mut self, h: &'b str) -> Self {
self.b.long_help = Some(h);
self
}
/// Specifies that this arg is the last, or final, positional argument (i.e. has the highest
/// index) and is *only* able to be accessed via the `--` syntax (i.e. `$ prog args --
/// last_arg`). Even, if no other arguments are left to parse, if the user omits the `--` syntax
/// they will receive an [`UnknownArgument`] error. Setting an argument to `.last(true)` also
/// allows one to access this arg early using the `--` syntax. Accessing an arg early, even with
/// the `--` syntax is otherwise not possible.
///
/// **NOTE:** This will change the usage string to look like `$ prog [FLAGS] [-- <ARG>]` if
/// `ARG` is marked as `.last(true)`.
///
/// **NOTE:** This setting will imply [`AppSettings::DontCollapseArgsInUsage`] because failing
/// to set this can make the usage string very confusing.
///
/// **NOTE**: This setting only applies to positional arguments, and has no affect on FLAGS /
/// OPTIONS
///
/// **CAUTION:** Setting an argument to `.last(true)` *and* having child subcommands is not
/// recommended with the exception of *also* using [`AppSettings::ArgsNegateSubcommands`]
/// (or [`AppSettings::SubcommandsNegateReqs`] if the argument marked `.last(true)` is also
/// marked [`.required(true)`])
///
/// # Examples
///
/// ```rust
/// # use clap::Arg;
/// Arg::with_name("args")
/// .last(true)
/// # ;
/// ```
///
/// Setting [`Arg::last(true)`] ensures the arg has the highest [index] of all positional args
/// and requires that the `--` syntax be used to access it early.
///
/// ```rust
/// # use clap::{App, Arg};
/// let res = App::new("prog")
/// .arg(Arg::with_name("first"))
/// .arg(Arg::with_name("second"))
/// .arg(Arg::with_name("third").last(true))
/// .get_matches_from_safe(vec![
/// "prog", "one", "--", "three"
/// ]);
///
/// assert!(res.is_ok());
/// let m = res.unwrap();
/// assert_eq!(m.value_of("third"), Some("three"));
/// assert!(m.value_of("second").is_none());
/// ```
///
/// Even if the positional argument marked `.last(true)` is the only argument left to parse,
/// failing to use the `--` syntax results in an error.
///
/// ```rust
/// # use clap::{App, Arg, ErrorKind};
/// let res = App::new("prog")
/// .arg(Arg::with_name("first"))
/// .arg(Arg::with_name("second"))
/// .arg(Arg::with_name("third").last(true))
/// .get_matches_from_safe(vec![
/// "prog", "one", "two", "three"
/// ]);
///
/// assert!(res.is_err());
/// assert_eq!(res.unwrap_err().kind, ErrorKind::UnknownArgument);
/// ```
/// [`Arg::last(true)`]: ./struct.Arg.html#method.last
/// [index]: ./struct.Arg.html#method.index
/// [`AppSettings::DontCollapseArgsInUsage`]: ./enum.AppSettings.html#variant.DontCollapseArgsInUsage
/// [`AppSettings::ArgsNegateSubcommands`]: ./enum.AppSettings.html#variant.ArgsNegateSubcommands
/// [`AppSettings::SubcommandsNegateReqs`]: ./enum.AppSettings.html#variant.SubcommandsNegateReqs
/// [`.required(true)`]: ./struct.Arg.html#method.required
/// [`UnknownArgument`]: ./enum.ErrorKind.html#variant.UnknownArgument
pub fn last(self, l: bool) -> Self {
if l {
self.set(ArgSettings::Last)
} else {
self.unset(ArgSettings::Last)
}
}
/// Sets whether or not the argument is required by default. Required by default means it is
/// required, when no other conflicting rules have been evaluated. Conflicting rules take
/// precedence over being required. **Default:** `false`
///
/// **NOTE:** Flags (i.e. not positional, or arguments that take values) cannot be required by
/// default. This is simply because if a flag should be required, it should simply be implied
/// as no additional information is required from user. Flags by their very nature are simply
/// yes/no, or true/false.
///
/// # Examples
///
/// ```rust
/// # use clap::Arg;
/// Arg::with_name("config")
/// .required(true)
/// # ;
/// ```
///
/// Setting [`Arg::required(true)`] requires that the argument be used at runtime.
///
/// ```rust
/// # use clap::{App, Arg};
/// let res = App::new("prog")
/// .arg(Arg::with_name("cfg")
/// .required(true)
/// .takes_value(true)
/// .long("config"))
/// .get_matches_from_safe(vec![
/// "prog", "--config", "file.conf"
/// ]);
///
/// assert!(res.is_ok());
/// ```
///
/// Setting [`Arg::required(true)`] and *not* supplying that argument is an error.
///
/// ```rust
/// # use clap::{App, Arg, ErrorKind};
/// let res = App::new("prog")
/// .arg(Arg::with_name("cfg")
/// .required(true)
/// .takes_value(true)
/// .long("config"))
/// .get_matches_from_safe(vec![
/// "prog"
/// ]);
///
/// assert!(res.is_err());
/// assert_eq!(res.unwrap_err().kind, ErrorKind::MissingRequiredArgument);
/// ```
/// [`Arg::required(true)`]: ./struct.Arg.html#method.required
pub fn required(self, r: bool) -> Self {
if r {
self.set(ArgSettings::Required)
} else {
self.unset(ArgSettings::Required)
}
}
/// Requires that options use the `--option=val` syntax (i.e. an equals between the option and
/// associated value) **Default:** `false`
///
/// **NOTE:** This setting also removes the default of allowing empty values and implies
/// [`Arg::empty_values(false)`].
///
/// # Examples
///
/// ```rust
/// # use clap::Arg;
/// Arg::with_name("config")
/// .long("config")
/// .takes_value(true)
/// .require_equals(true)
/// # ;
/// ```
///
/// Setting [`Arg::require_equals(true)`] requires that the option have an equals sign between
/// it and the associated value.
///
/// ```rust
/// # use clap::{App, Arg};
/// let res = App::new("prog")
/// .arg(Arg::with_name("cfg")
/// .require_equals(true)
/// .takes_value(true)
/// .long("config"))
/// .get_matches_from_safe(vec![
/// "prog", "--config=file.conf"
/// ]);
///
/// assert!(res.is_ok());
/// ```
///
/// Setting [`Arg::require_equals(true)`] and *not* supplying the equals will cause an error
/// unless [`Arg::empty_values(true)`] is set.
///
/// ```rust
/// # use clap::{App, Arg, ErrorKind};
/// let res = App::new("prog")
/// .arg(Arg::with_name("cfg")
/// .require_equals(true)
/// .takes_value(true)
/// .long("config"))
/// .get_matches_from_safe(vec![
/// "prog", "--config", "file.conf"
/// ]);
///
/// assert!(res.is_err());
/// assert_eq!(res.unwrap_err().kind, ErrorKind::EmptyValue);
/// ```
/// [`Arg::require_equals(true)`]: ./struct.Arg.html#method.require_equals
/// [`Arg::empty_values(true)`]: ./struct.Arg.html#method.empty_values
/// [`Arg::empty_values(false)`]: ./struct.Arg.html#method.empty_values
pub fn require_equals(mut self, r: bool) -> Self {
if r {
self.unsetb(ArgSettings::EmptyValues);
self.set(ArgSettings::RequireEquals)
} else {
self.unset(ArgSettings::RequireEquals)
}
}
/// Allows values which start with a leading hyphen (`-`)
///
/// **WARNING**: Take caution when using this setting, combined with [`Arg::multiple(true)`] as
/// it this becomes ambigous `$ prog --arg -- -- val`. All three `--, --, val` will be values
/// when the user may have thought the second `--` would constitute the normal, "Only
/// positional args follow" idiom. To fix this, consider using [`Arg::number_of_values(1)`]
///
/// **WARNING**: When building your CLIs, consider the effects of allowing leading hyphens and
/// the user passing in a value that matches a valid short. For example `prog -opt -F` where
/// `-F` is supposed to be a value, yet `-F` is *also* a valid short for anther arg. Care should
/// should be taken when designing these args. This is compounded by the ability to "stack"
/// short args. I.e. if `-val` is supposed to be a value, but `-v`, `-a`, and `-l` are all valid
/// shorts.
///
/// # Examples
///
/// ```rust
/// # use clap::Arg;
/// Arg::with_name("pattern")
/// .allow_hyphen_values(true)
/// # ;
/// ```
///
/// ```rust
/// # use clap::{App, Arg};
/// let m = App::new("prog")
/// .arg(Arg::with_name("pat")
/// .allow_hyphen_values(true)
/// .takes_value(true)
/// .long("pattern"))
/// .get_matches_from(vec![
/// "prog", "--pattern", "-file"
/// ]);
///
/// assert_eq!(m.value_of("pat"), Some("-file"));
/// ```
///
/// Not setting [`Arg::allow_hyphen_values(true)`] and supplying a value which starts with a
/// hyphen is an error.
///
/// ```rust
/// # use clap::{App, Arg, ErrorKind};
/// let res = App::new("prog")
/// .arg(Arg::with_name("pat")
/// .takes_value(true)
/// .long("pattern"))
/// .get_matches_from_safe(vec![
/// "prog", "--pattern", "-file"
/// ]);
///
/// assert!(res.is_err());
/// assert_eq!(res.unwrap_err().kind, ErrorKind::UnknownArgument);
/// ```
/// [`Arg::allow_hyphen_values(true)`]: ./struct.Arg.html#method.allow_hyphen_values
/// [`Arg::multiple(true)`]: ./struct.Arg.html#method.multiple
/// [`Arg::number_of_values(1)`]: ./struct.Arg.html#method.number_of_values
pub fn allow_hyphen_values(self, a: bool) -> Self {
if a {
self.set(ArgSettings::AllowLeadingHyphen)
} else {
self.unset(ArgSettings::AllowLeadingHyphen)
}
}
/// Sets an arg that override this arg's required setting. (i.e. this arg will be required
/// unless this other argument is present).
///
/// **Pro Tip:** Using [`Arg::required_unless`] implies [`Arg::required`] and is therefore not
/// mandatory to also set.
///
/// # Examples
///
/// ```rust
/// # use clap::Arg;
/// Arg::with_name("config")
/// .required_unless("debug")
/// # ;
/// ```
///
/// Setting [`Arg::required_unless(name)`] requires that the argument be used at runtime
/// *unless* `name` is present. In the following example, the required argument is *not*
/// provided, but it's not an error because the `unless` arg has been supplied.
///
/// ```rust
/// # use clap::{App, Arg};
/// let res = App::new("prog")
/// .arg(Arg::with_name("cfg")
/// .required_unless("dbg")
/// .takes_value(true)
/// .long("config"))
/// .arg(Arg::with_name("dbg")
/// .long("debug"))
/// .get_matches_from_safe(vec![
/// "prog", "--debug"
/// ]);
///
/// assert!(res.is_ok());
/// ```
///
/// Setting [`Arg::required_unless(name)`] and *not* supplying `name` or this arg is an error.
///
/// ```rust
/// # use clap::{App, Arg, ErrorKind};
/// let res = App::new("prog")
/// .arg(Arg::with_name("cfg")
/// .required_unless("dbg")
/// .takes_value(true)
/// .long("config"))
/// .arg(Arg::with_name("dbg")
/// .long("debug"))
/// .get_matches_from_safe(vec![
/// "prog"
/// ]);
///
/// assert!(res.is_err());
/// assert_eq!(res.unwrap_err().kind, ErrorKind::MissingRequiredArgument);
/// ```
/// [`Arg::required_unless`]: ./struct.Arg.html#method.required_unless
/// [`Arg::required`]: ./struct.Arg.html#method.required
/// [`Arg::required_unless(name)`]: ./struct.Arg.html#method.required_unless
pub fn required_unless(mut self, name: &'a str) -> Self {
if let Some(ref mut vec) = self.b.r_unless {
vec.push(name);
} else {
self.b.r_unless = Some(vec![name]);
}
self.required(true)
}
/// Sets args that override this arg's required setting. (i.e. this arg will be required unless
/// all these other arguments are present).
///
/// **NOTE:** If you wish for this argument to only be required if *one of* these args are
/// present see [`Arg::required_unless_one`]
///
/// # Examples
///
/// ```rust
/// # use clap::Arg;
/// Arg::with_name("config")
/// .required_unless_all(&["cfg", "dbg"])
/// # ;
/// ```
///
/// Setting [`Arg::required_unless_all(names)`] requires that the argument be used at runtime
/// *unless* *all* the args in `names` are present. In the following example, the required
/// argument is *not* provided, but it's not an error because all the `unless` args have been
/// supplied.
///
/// ```rust
/// # use clap::{App, Arg};
/// let res = App::new("prog")
/// .arg(Arg::with_name("cfg")
/// .required_unless_all(&["dbg", "infile"])
/// .takes_value(true)
/// .long("config"))
/// .arg(Arg::with_name("dbg")
/// .long("debug"))
/// .arg(Arg::with_name("infile")
/// .short("i")
/// .takes_value(true))
/// .get_matches_from_safe(vec![
/// "prog", "--debug", "-i", "file"
/// ]);
///
/// assert!(res.is_ok());
/// ```
///
/// Setting [`Arg::required_unless_all(names)`] and *not* supplying *all* of `names` or this
/// arg is an error.
///
/// ```rust
/// # use clap::{App, Arg, ErrorKind};
/// let res = App::new("prog")
/// .arg(Arg::with_name("cfg")
/// .required_unless_all(&["dbg", "infile"])
/// .takes_value(true)
/// .long("config"))
/// .arg(Arg::with_name("dbg")
/// .long("debug"))
/// .arg(Arg::with_name("infile")
/// .short("i")
/// .takes_value(true))
/// .get_matches_from_safe(vec![
/// "prog"
/// ]);
///
/// assert!(res.is_err());
/// assert_eq!(res.unwrap_err().kind, ErrorKind::MissingRequiredArgument);
/// ```
/// [`Arg::required_unless_one`]: ./struct.Arg.html#method.required_unless_one
/// [`Arg::required_unless_all(names)`]: ./struct.Arg.html#method.required_unless_all
pub fn required_unless_all(mut self, names: &[&'a str]) -> Self {
if let Some(ref mut vec) = self.b.r_unless {
for s in names {
vec.push(s);
}
} else {
self.b.r_unless = Some(names.iter().map(|s| *s).collect::<Vec<_>>());
}
self.setb(ArgSettings::RequiredUnlessAll);
self.required(true)
}
/// Sets args that override this arg's [required] setting. (i.e. this arg will be required
/// unless *at least one of* these other arguments are present).
///
/// **NOTE:** If you wish for this argument to only be required if *all of* these args are
/// present see [`Arg::required_unless_all`]
///
/// # Examples
///
/// ```rust
/// # use clap::Arg;
/// Arg::with_name("config")
/// .required_unless_all(&["cfg", "dbg"])
/// # ;
/// ```
///
/// Setting [`Arg::required_unless_one(names)`] requires that the argument be used at runtime
/// *unless* *at least one of* the args in `names` are present. In the following example, the
/// required argument is *not* provided, but it's not an error because one the `unless` args
/// have been supplied.
///
/// ```rust
/// # use clap::{App, Arg};
/// let res = App::new("prog")
/// .arg(Arg::with_name("cfg")
/// .required_unless_one(&["dbg", "infile"])
/// .takes_value(true)
/// .long("config"))
/// .arg(Arg::with_name("dbg")
/// .long("debug"))
/// .arg(Arg::with_name("infile")
/// .short("i")
/// .takes_value(true))
/// .get_matches_from_safe(vec![
/// "prog", "--debug"
/// ]);
///
/// assert!(res.is_ok());
/// ```
///
/// Setting [`Arg::required_unless_one(names)`] and *not* supplying *at least one of* `names`
/// or this arg is an error.
///
/// ```rust
/// # use clap::{App, Arg, ErrorKind};
/// let res = App::new("prog")
/// .arg(Arg::with_name("cfg")
/// .required_unless_one(&["dbg", "infile"])
/// .takes_value(true)
/// .long("config"))
/// .arg(Arg::with_name("dbg")
/// .long("debug"))
/// .arg(Arg::with_name("infile")
/// .short("i")
/// .takes_value(true))
/// .get_matches_from_safe(vec![
/// "prog"
/// ]);
///
/// assert!(res.is_err());
/// assert_eq!(res.unwrap_err().kind, ErrorKind::MissingRequiredArgument);
/// ```
/// [required]: ./struct.Arg.html#method.required
/// [`Arg::required_unless_one(names)`]: ./struct.Arg.html#method.required_unless_one
/// [`Arg::required_unless_all`]: ./struct.Arg.html#method.required_unless_all
pub fn required_unless_one(mut self, names: &[&'a str]) -> Self {
if let Some(ref mut vec) = self.b.r_unless {
for s in names {
vec.push(s);
}
} else {
self.b.r_unless = Some(names.iter().map(|s| *s).collect::<Vec<_>>());
}
self.required(true)
}
/// Sets a conflicting argument by name. I.e. when using this argument,
/// the following argument can't be present and vice versa.
///
/// **NOTE:** Conflicting rules take precedence over being required by default. Conflict rules
/// only need to be set for one of the two arguments, they do not need to be set for each.
///
/// **NOTE:** Defining a conflict is two-way, but does *not* need to defined for both arguments
/// (i.e. if A conflicts with B, defining A.conflicts_with(B) is sufficient. You do not need
/// need to also do B.conflicts_with(A))
///
/// # Examples
///
/// ```rust
/// # use clap::Arg;
/// Arg::with_name("config")
/// .conflicts_with("debug")
/// # ;
/// ```
///
/// Setting conflicting argument, and having both arguments present at runtime is an error.
///
/// ```rust
/// # use clap::{App, Arg, ErrorKind};
/// let res = App::new("prog")
/// .arg(Arg::with_name("cfg")
/// .takes_value(true)
/// .conflicts_with("debug")
/// .long("config"))
/// .arg(Arg::with_name("debug")
/// .long("debug"))
/// .get_matches_from_safe(vec![
/// "prog", "--debug", "--config", "file.conf"
/// ]);
///
/// assert!(res.is_err());
/// assert_eq!(res.unwrap_err().kind, ErrorKind::ArgumentConflict);
/// ```
pub fn conflicts_with(mut self, name: &'a str) -> Self {
if let Some(ref mut vec) = self.b.blacklist {
vec.push(name);
} else {
self.b.blacklist = Some(vec![name]);
}
self
}
/// The same as [`Arg::conflicts_with`] but allows specifying multiple two-way conlicts per
/// argument.
///
/// **NOTE:** Conflicting rules take precedence over being required by default. Conflict rules
/// only need to be set for one of the two arguments, they do not need to be set for each.
///
/// **NOTE:** Defining a conflict is two-way, but does *not* need to defined for both arguments
/// (i.e. if A conflicts with B, defining A.conflicts_with(B) is sufficient. You do not need
/// need to also do B.conflicts_with(A))
///
/// # Examples
///
/// ```rust
/// # use clap::Arg;
/// Arg::with_name("config")
/// .conflicts_with_all(&["debug", "input"])
/// # ;
/// ```
///
/// Setting conflicting argument, and having any of the arguments present at runtime with a
/// conflicting argument is an error.
///
/// ```rust
/// # use clap::{App, Arg, ErrorKind};
/// let res = App::new("prog")
/// .arg(Arg::with_name("cfg")
/// .takes_value(true)
/// .conflicts_with_all(&["debug", "input"])
/// .long("config"))
/// .arg(Arg::with_name("debug")
/// .long("debug"))
/// .arg(Arg::with_name("input")
/// .index(1))
/// .get_matches_from_safe(vec![
/// "prog", "--config", "file.conf", "file.txt"
/// ]);
///
/// assert!(res.is_err());
/// assert_eq!(res.unwrap_err().kind, ErrorKind::ArgumentConflict);
/// ```
/// [`Arg::conflicts_with`]: ./struct.Arg.html#method.conflicts_with
pub fn conflicts_with_all(mut self, names: &[&'a str]) -> Self {
if let Some(ref mut vec) = self.b.blacklist {
for s in names {
vec.push(s);
}
} else {
self.b.blacklist = Some(names.iter().map(|s| *s).collect::<Vec<_>>());
}
self
}
/// Sets a overridable argument by name. I.e. this argument and the following argument
/// will override each other in POSIX style (whichever argument was specified at runtime
/// **last** "wins")
///
/// **NOTE:** When an argument is overridden it is essentially as if it never was used, any
/// conflicts, requirements, etc. are evaluated **after** all "overrides" have been removed
///
/// # Examples
///
/// ```rust
/// # use clap::{App, Arg};
/// let m = App::new("prog")
/// .arg(Arg::from_usage("-f, --flag 'some flag'")
/// .conflicts_with("debug"))
/// .arg(Arg::from_usage("-d, --debug 'other flag'"))
/// .arg(Arg::from_usage("-c, --color 'third flag'")
/// .overrides_with("flag"))
/// .get_matches_from(vec![
/// "prog", "-f", "-d", "-c"]);
/// // ^~~~~~~~~~~~^~~~~ flag is overridden by color
///
/// assert!(m.is_present("color"));
/// assert!(m.is_present("debug")); // even though flag conflicts with debug, it's as if flag
/// // was never used because it was overridden with color
/// assert!(!m.is_present("flag"));
/// ```
pub fn overrides_with(mut self, name: &'a str) -> Self {
if let Some(ref mut vec) = self.b.overrides {
vec.push(name.as_ref());
} else {
self.b.overrides = Some(vec![name.as_ref()]);
}
self
}
/// Sets multiple mutually overridable arguments by name. I.e. this argument and the following
/// argument will override each other in POSIX style (whichever argument was specified at
/// runtime **last** "wins")
///
/// **NOTE:** When an argument is overridden it is essentially as if it never was used, any
/// conflicts, requirements, etc. are evaluated **after** all "overrides" have been removed
///
/// # Examples
///
/// ```rust
/// # use clap::{App, Arg};
/// let m = App::new("prog")
/// .arg(Arg::from_usage("-f, --flag 'some flag'")
/// .conflicts_with("color"))
/// .arg(Arg::from_usage("-d, --debug 'other flag'"))
/// .arg(Arg::from_usage("-c, --color 'third flag'")
/// .overrides_with_all(&["flag", "debug"]))
/// .get_matches_from(vec![
/// "prog", "-f", "-d", "-c"]);
/// // ^~~~~~^~~~~~~~~ flag and debug are overridden by color
///
/// assert!(m.is_present("color")); // even though flag conflicts with color, it's as if flag
/// // and debug were never used because they were overridden
/// // with color
/// assert!(!m.is_present("debug"));
/// assert!(!m.is_present("flag"));
/// ```
pub fn overrides_with_all(mut self, names: &[&'a str]) -> Self {
if let Some(ref mut vec) = self.b.overrides {
for s in names {
vec.push(s);
}
} else {
self.b.overrides = Some(names.iter().map(|s| *s).collect::<Vec<_>>());
}
self
}
/// Sets an argument by name that is required when this one is present I.e. when
/// using this argument, the following argument *must* be present.
///
/// **NOTE:** [Conflicting] rules and [override] rules take precedence over being required
///
/// # Examples
///
/// ```rust
/// # use clap::Arg;
/// Arg::with_name("config")
/// .requires("input")
/// # ;
/// ```
///
/// Setting [`Arg::requires(name)`] requires that the argument be used at runtime if the
/// defining argument is used. If the defining argument isn't used, the other argument isn't
/// required
///
/// ```rust
/// # use clap::{App, Arg};
/// let res = App::new("prog")
/// .arg(Arg::with_name("cfg")
/// .takes_value(true)
/// .requires("input")
/// .long("config"))
/// .arg(Arg::with_name("input")
/// .index(1))
/// .get_matches_from_safe(vec![
/// "prog"
/// ]);
///
/// assert!(res.is_ok()); // We didn't use cfg, so input wasn't required
/// ```
///
/// Setting [`Arg::requires(name)`] and *not* supplying that argument is an error.
///
/// ```rust
/// # use clap::{App, Arg, ErrorKind};
/// let res = App::new("prog")
/// .arg(Arg::with_name("cfg")
/// .takes_value(true)
/// .requires("input")
/// .long("config"))
/// .arg(Arg::with_name("input")
/// .index(1))
/// .get_matches_from_safe(vec![
/// "prog", "--config", "file.conf"
/// ]);
///
/// assert!(res.is_err());
/// assert_eq!(res.unwrap_err().kind, ErrorKind::MissingRequiredArgument);
/// ```
/// [`Arg::requires(name)`]: ./struct.Arg.html#method.requires
/// [Conflicting]: ./struct.Arg.html#method.conflicts_with
/// [override]: ./struct.Arg.html#method.overrides_with
pub fn requires(mut self, name: &'a str) -> Self {
if let Some(ref mut vec) = self.b.requires {
vec.push((None, name));
} else {
let mut vec = vec![];
vec.push((None, name));
self.b.requires = Some(vec);
}
self
}
/// Allows a conditional requirement. The requirement will only become valid if this arg's value
/// equals `val`.
///
/// **NOTE:** If using YAML the values should be laid out as follows
///
/// ```yaml
/// requires_if:
/// - [val, arg]
/// ```
///
/// # Examples
///
/// ```rust
/// # use clap::Arg;
/// Arg::with_name("config")
/// .requires_if("val", "arg")
/// # ;
/// ```
///
/// Setting [`Arg::requires_if(val, arg)`] requires that the `arg` be used at runtime if the
/// defining argument's value is equal to `val`. If the defining argument is anything other than
/// `val`, the other argument isn't required.
///
/// ```rust
/// # use clap::{App, Arg};
/// let res = App::new("prog")
/// .arg(Arg::with_name("cfg")
/// .takes_value(true)
/// .requires_if("my.cfg", "other")
/// .long("config"))
/// .arg(Arg::with_name("other"))
/// .get_matches_from_safe(vec![
/// "prog", "--config", "some.cfg"
/// ]);
///
/// assert!(res.is_ok()); // We didn't use --config=my.cfg, so other wasn't required
/// ```
///
/// Setting [`Arg::requires_if(val, arg)`] and setting the value to `val` but *not* supplying
/// `arg` is an error.
///
/// ```rust
/// # use clap::{App, Arg, ErrorKind};
/// let res = App::new("prog")
/// .arg(Arg::with_name("cfg")
/// .takes_value(true)
/// .requires_if("my.cfg", "input")
/// .long("config"))
/// .arg(Arg::with_name("input"))
/// .get_matches_from_safe(vec![
/// "prog", "--config", "my.cfg"
/// ]);
///
/// assert!(res.is_err());
/// assert_eq!(res.unwrap_err().kind, ErrorKind::MissingRequiredArgument);
/// ```
/// [`Arg::requires(name)`]: ./struct.Arg.html#method.requires
/// [Conflicting]: ./struct.Arg.html#method.conflicts_with
/// [override]: ./struct.Arg.html#method.overrides_with
pub fn requires_if(mut self, val: &'b str, arg: &'a str) -> Self {
if let Some(ref mut vec) = self.b.requires {
vec.push((Some(val), arg));
} else {
self.b.requires = Some(vec![(Some(val), arg)]);
}
self
}
/// Allows multiple conditional requirements. The requirement will only become valid if this arg's value
/// equals `val`.
///
/// **NOTE:** If using YAML the values should be laid out as follows
///
/// ```yaml
/// requires_if:
/// - [val, arg]
/// - [val2, arg2]
/// ```
///
/// # Examples
///
/// ```rust
/// # use clap::Arg;
/// Arg::with_name("config")
/// .requires_ifs(&[
/// ("val", "arg"),
/// ("other_val", "arg2"),
/// ])
/// # ;
/// ```
///
/// Setting [`Arg::requires_ifs(&["val", "arg"])`] requires that the `arg` be used at runtime if the
/// defining argument's value is equal to `val`. If the defining argument's value is anything other
/// than `val`, `arg` isn't required.
///
/// ```rust
/// # use clap::{App, Arg, ErrorKind};
/// let res = App::new("prog")
/// .arg(Arg::with_name("cfg")
/// .takes_value(true)
/// .requires_ifs(&[
/// ("special.conf", "opt"),
/// ("other.conf", "other"),
/// ])
/// .long("config"))
/// .arg(Arg::with_name("opt")
/// .long("option")
/// .takes_value(true))
/// .arg(Arg::with_name("other"))
/// .get_matches_from_safe(vec![
/// "prog", "--config", "special.conf"
/// ]);
///
/// assert!(res.is_err()); // We used --config=special.conf so --option <val> is required
/// assert_eq!(res.unwrap_err().kind, ErrorKind::MissingRequiredArgument);
/// ```
/// [`Arg::requires(name)`]: ./struct.Arg.html#method.requires
/// [Conflicting]: ./struct.Arg.html#method.conflicts_with
/// [override]: ./struct.Arg.html#method.overrides_with
pub fn requires_ifs(mut self, ifs: &[(&'b str, &'a str)]) -> Self {
if let Some(ref mut vec) = self.b.requires {
for &(val, arg) in ifs {
vec.push((Some(val), arg));
}
} else {
let mut vec = vec![];
for &(val, arg) in ifs {
vec.push((Some(val), arg));
}
self.b.requires = Some(vec);
}
self
}
/// Allows specifying that an argument is [required] conditionally. The requirement will only
/// become valid if the specified `arg`'s value equals `val`.
///
/// **NOTE:** If using YAML the values should be laid out as follows
///
/// ```yaml
/// required_if:
/// - [arg, val]
/// ```
///
/// # Examples
///
/// ```rust
/// # use clap::Arg;
/// Arg::with_name("config")
/// .required_if("other_arg", "value")
/// # ;
/// ```
///
/// Setting [`Arg::required_if(arg, val)`] makes this arg required if the `arg` is used at
/// runtime and it's value is equal to `val`. If the `arg`'s value is anything other than `val`,
/// this argument isn't required.
///
/// ```rust
/// # use clap::{App, Arg};
/// let res = App::new("prog")
/// .arg(Arg::with_name("cfg")
/// .takes_value(true)
/// .required_if("other", "special")
/// .long("config"))
/// .arg(Arg::with_name("other")
/// .long("other")
/// .takes_value(true))
/// .get_matches_from_safe(vec![
/// "prog", "--other", "not-special"
/// ]);
///
/// assert!(res.is_ok()); // We didn't use --other=special, so "cfg" wasn't required
/// ```
///
/// Setting [`Arg::required_if(arg, val)`] and having `arg` used with a value of `val` but *not*
/// using this arg is an error.
///
/// ```rust
/// # use clap::{App, Arg, ErrorKind};
/// let res = App::new("prog")
/// .arg(Arg::with_name("cfg")
/// .takes_value(true)
/// .required_if("other", "special")
/// .long("config"))
/// .arg(Arg::with_name("other")
/// .long("other")
/// .takes_value(true))
/// .get_matches_from_safe(vec![
/// "prog", "--other", "special"
/// ]);
///
/// assert!(res.is_err());
/// assert_eq!(res.unwrap_err().kind, ErrorKind::MissingRequiredArgument);
/// ```
/// [`Arg::requires(name)`]: ./struct.Arg.html#method.requires
/// [Conflicting]: ./struct.Arg.html#method.conflicts_with
/// [required]: ./struct.Arg.html#method.required
pub fn required_if(mut self, arg: &'a str, val: &'b str) -> Self {
if let Some(ref mut vec) = self.r_ifs {
vec.push((arg, val));
} else {
self.r_ifs = Some(vec![(arg, val)]);
}
self
}
/// Allows specifying that an argument is [required] based on multiple conditions. The
/// conditions are set up in a `(arg, val)` style tuple. The requirement will only become valid
/// if one of the specified `arg`'s value equals it's corresponding `val`.
///
/// **NOTE:** If using YAML the values should be laid out as follows
///
/// ```yaml
/// required_if:
/// - [arg, val]
/// - [arg2, val2]
/// ```
///
/// # Examples
///
/// ```rust
/// # use clap::Arg;
/// Arg::with_name("config")
/// .required_ifs(&[
/// ("extra", "val"),
/// ("option", "spec")
/// ])
/// # ;
/// ```
///
/// Setting [`Arg::required_ifs(&[(arg, val)])`] makes this arg required if any of the `arg`s
/// are used at runtime and it's corresponding value is equal to `val`. If the `arg`'s value is
/// anything other than `val`, this argument isn't required.
///
/// ```rust
/// # use clap::{App, Arg};
/// let res = App::new("prog")
/// .arg(Arg::with_name("cfg")
/// .required_ifs(&[
/// ("extra", "val"),
/// ("option", "spec")
/// ])
/// .takes_value(true)
/// .long("config"))
/// .arg(Arg::with_name("extra")
/// .takes_value(true)
/// .long("extra"))
/// .arg(Arg::with_name("option")
/// .takes_value(true)
/// .long("option"))
/// .get_matches_from_safe(vec![
/// "prog", "--option", "other"
/// ]);
///
/// assert!(res.is_ok()); // We didn't use --option=spec, or --extra=val so "cfg" isn't required
/// ```
///
/// Setting [`Arg::required_ifs(&[(arg, val)])`] and having any of the `arg`s used with it's
/// value of `val` but *not* using this arg is an error.
///
/// ```rust
/// # use clap::{App, Arg, ErrorKind};
/// let res = App::new("prog")
/// .arg(Arg::with_name("cfg")
/// .required_ifs(&[
/// ("extra", "val"),
/// ("option", "spec")
/// ])
/// .takes_value(true)
/// .long("config"))
/// .arg(Arg::with_name("extra")
/// .takes_value(true)
/// .long("extra"))
/// .arg(Arg::with_name("option")
/// .takes_value(true)
/// .long("option"))
/// .get_matches_from_safe(vec![
/// "prog", "--option", "spec"
/// ]);
///
/// assert!(res.is_err());
/// assert_eq!(res.unwrap_err().kind, ErrorKind::MissingRequiredArgument);
/// ```
/// [`Arg::requires(name)`]: ./struct.Arg.html#method.requires
/// [Conflicting]: ./struct.Arg.html#method.conflicts_with
/// [required]: ./struct.Arg.html#method.required
pub fn required_ifs(mut self, ifs: &[(&'a str, &'b str)]) -> Self {
if let Some(ref mut vec) = self.r_ifs {
for r_if in ifs {
vec.push((r_if.0, r_if.1));
}
} else {
let mut vec = vec![];
for r_if in ifs {
vec.push((r_if.0, r_if.1));
}
self.r_ifs = Some(vec);
}
self
}
/// Sets multiple arguments by names that are required when this one is present I.e. when
/// using this argument, the following arguments *must* be present.
///
/// **NOTE:** [Conflicting] rules and [override] rules take precedence over being required
/// by default.
///
/// # Examples
///
/// ```rust
/// # use clap::Arg;
/// Arg::with_name("config")
/// .requires_all(&["input", "output"])
/// # ;
/// ```
///
/// Setting [`Arg::requires_all(&[arg, arg2])`] requires that all the arguments be used at
/// runtime if the defining argument is used. If the defining argument isn't used, the other
/// argument isn't required
///
/// ```rust
/// # use clap::{App, Arg};
/// let res = App::new("prog")
/// .arg(Arg::with_name("cfg")
/// .takes_value(true)
/// .requires("input")
/// .long("config"))
/// .arg(Arg::with_name("input")
/// .index(1))
/// .arg(Arg::with_name("output")
/// .index(2))
/// .get_matches_from_safe(vec![
/// "prog"
/// ]);
///
/// assert!(res.is_ok()); // We didn't use cfg, so input and output weren't required
/// ```
///
/// Setting [`Arg::requires_all(&[arg, arg2])`] and *not* supplying all the arguments is an
/// error.
///
/// ```rust
/// # use clap::{App, Arg, ErrorKind};
/// let res = App::new("prog")
/// .arg(Arg::with_name("cfg")
/// .takes_value(true)
/// .requires_all(&["input", "output"])
/// .long("config"))
/// .arg(Arg::with_name("input")
/// .index(1))
/// .arg(Arg::with_name("output")
/// .index(2))
/// .get_matches_from_safe(vec![
/// "prog", "--config", "file.conf", "in.txt"
/// ]);
///
/// assert!(res.is_err());
/// // We didn't use output
/// assert_eq!(res.unwrap_err().kind, ErrorKind::MissingRequiredArgument);
/// ```
/// [Conflicting]: ./struct.Arg.html#method.conflicts_with
/// [override]: ./struct.Arg.html#method.overrides_with
/// [`Arg::requires_all(&[arg, arg2])`]: ./struct.Arg.html#method.requires_all
pub fn requires_all(mut self, names: &[&'a str]) -> Self {
if let Some(ref mut vec) = self.b.requires {
for s in names {
vec.push((None, s));
}
} else {
let mut vec = vec![];
for s in names {
vec.push((None, *s));
}
self.b.requires = Some(vec);
}
self
}
/// Specifies that the argument takes a value at run time.
///
/// **NOTE:** values for arguments may be specified in any of the following methods
///
/// * Using a space such as `-o value` or `--option value`
/// * Using an equals and no space such as `-o=value` or `--option=value`
/// * Use a short and no space such as `-ovalue`
///
/// **NOTE:** By default, args which allow [multiple values] are delimited by commas, meaning
/// `--option=val1,val2,val3` is three values for the `--option` argument. If you wish to
/// change the delimiter to another character you can use [`Arg::value_delimiter(char)`],
/// alternatively you can turn delimiting values **OFF** by using [`Arg::use_delimiter(false)`]
///
/// # Examples
///
/// ```rust
/// # use clap::{App, Arg};
/// Arg::with_name("config")
/// .takes_value(true)
/// # ;
/// ```
///
/// ```rust
/// # use clap::{App, Arg};
/// let m = App::new("prog")
/// .arg(Arg::with_name("mode")
/// .long("mode")
/// .takes_value(true))
/// .get_matches_from(vec![
/// "prog", "--mode", "fast"
/// ]);
///
/// assert!(m.is_present("mode"));
/// assert_eq!(m.value_of("mode"), Some("fast"));
/// ```
/// [`Arg::value_delimiter(char)`]: ./struct.Arg.html#method.value_delimiter
/// [`Arg::use_delimiter(false)`]: ./struct.Arg.html#method.use_delimiter
/// [multiple values]: ./struct.Arg.html#method.multiple
pub fn takes_value(self, tv: bool) -> Self {
if tv {
self.set(ArgSettings::TakesValue)
} else {
self.unset(ArgSettings::TakesValue)
}
}
/// Specifies if the possible values of an argument should be displayed in the help text or
/// not. Defaults to `false` (i.e. show possible values)
///
/// This is useful for args with many values, or ones which are explained elsewhere in the
/// help text.
///
/// # Examples
///
/// ```rust
/// # use clap::{App, Arg};
/// Arg::with_name("config")
/// .hide_possible_values(true)
/// # ;
/// ```
///
/// ```rust
/// # use clap::{App, Arg};
/// let m = App::new("prog")
/// .arg(Arg::with_name("mode")
/// .long("mode")
/// .possible_values(&["fast", "slow"])
/// .takes_value(true)
/// .hide_possible_values(true));
///
/// ```
///
/// If we were to run the above program with `--help` the `[values: fast, slow]` portion of
/// the help text would be omitted.
pub fn hide_possible_values(self, hide: bool) -> Self {
if hide {
self.set(ArgSettings::HidePossibleValues)
} else {
self.unset(ArgSettings::HidePossibleValues)
}
}
/// Specifies if the default value of an argument should be displayed in the help text or
/// not. Defaults to `false` (i.e. show default value)
///
/// This is useful when default behavior of an arg is explained elsewhere in the help text.
///
/// # Examples
///
/// ```rust
/// # use clap::{App, Arg};
/// Arg::with_name("config")
/// .hide_default_value(true)
/// # ;
/// ```
///
/// ```rust
/// # use clap::{App, Arg};
/// let m = App::new("connect")
/// .arg(Arg::with_name("host")
/// .long("host")
/// .default_value("localhost")
/// .hide_default_value(true));
///
/// ```
///
/// If we were to run the above program with `--help` the `[default: localhost]` portion of
/// the help text would be omitted.
pub fn hide_default_value(self, hide: bool) -> Self {
if hide {
self.set(ArgSettings::HideDefaultValue)
} else {
self.unset(ArgSettings::HideDefaultValue)
}
}
/// Specifies the index of a positional argument **starting at** 1.
///
/// **NOTE:** The index refers to position according to **other positional argument**. It does
/// not define position in the argument list as a whole.
///
/// **NOTE:** If no [`Arg::short`], or [`Arg::long`] have been defined, you can optionally
/// leave off the `index` method, and the index will be assigned in order of evaluation.
/// Utilizing the `index` method allows for setting indexes out of order
///
/// **NOTE:** When utilized with [`Arg::multiple(true)`], only the **last** positional argument
/// may be defined as multiple (i.e. with the highest index)
///
/// # Panics
///
/// Although not in this method directly, [`App`] will [`panic!`] if indexes are skipped (such
/// as defining `index(1)` and `index(3)` but not `index(2)`, or a positional argument is
/// defined as multiple and is not the highest index
///
/// # Examples
///
/// ```rust
/// # use clap::{App, Arg};
/// Arg::with_name("config")
/// .index(1)
/// # ;
/// ```
///
/// ```rust
/// # use clap::{App, Arg};
/// let m = App::new("prog")
/// .arg(Arg::with_name("mode")
/// .index(1))
/// .arg(Arg::with_name("debug")
/// .long("debug"))
/// .get_matches_from(vec![
/// "prog", "--debug", "fast"
/// ]);
///
/// assert!(m.is_present("mode"));
/// assert_eq!(m.value_of("mode"), Some("fast")); // notice index(1) means "first positional"
/// // *not* first argument
/// ```
/// [`Arg::short`]: ./struct.Arg.html#method.short
/// [`Arg::long`]: ./struct.Arg.html#method.long
/// [`Arg::multiple(true)`]: ./struct.Arg.html#method.multiple
/// [`App`]: ./struct.App.html
/// [`panic!`]: https://doc.rust-lang.org/std/macro.panic!.html
pub fn index(mut self, idx: u64) -> Self {
self.index = Some(idx);
self
}
/// Specifies that the argument may appear more than once. For flags, this results
/// in the number of occurrences of the flag being recorded. For example `-ddd` or `-d -d -d`
/// would count as three occurrences. For options there is a distinct difference in multiple
/// occurrences vs multiple values.
///
/// For example, `--opt val1 val2` is one occurrence, but two values. Whereas
/// `--opt val1 --opt val2` is two occurrences.
///
/// **WARNING:**
///
/// Setting `multiple(true)` for an [option] with no other details, allows multiple values
/// **and** multiple occurrences because it isn't possible to have more occurrences than values
/// for options. Because multiple values are allowed, `--option val1 val2 val3` is perfectly
/// valid, be careful when designing a CLI where positional arguments are expected after a
/// option which accepts multiple values, as `clap` will continue parsing *values* until it
/// reaches the max or specific number of values defined, or another flag or option.
///
/// **Pro Tip**:
///
/// It's possible to define an option which allows multiple occurrences, but only one value per
/// occurrence. To do this use [`Arg::number_of_values(1)`] in coordination with
/// [`Arg::multiple(true)`].
///
/// **WARNING:**
///
/// When using args with `multiple(true)` on [options] or [positionals] (i.e. those args that
/// accept values) and [subcommands], one needs to consider the posibility of an argument value
/// being the same as a valid subcommand. By default `clap` will parse the argument in question
/// as a value *only if* a value is possible at that moment. Otherwise it will be parsed as a
/// subcommand. In effect, this means using `multiple(true)` with no additional parameters and
/// a possible value that coincides with a subcommand name, the subcommand cannot be called
/// unless another argument is passed first.
///
/// As an example, consider a CLI with an option `--ui-paths=<paths>...` and subcommand `signer`
///
/// The following would be parsed as values to `--ui-paths`.
///
/// ```notrust
/// $ program --ui-paths path1 path2 signer
/// ```
///
/// This is because `--ui-paths` accepts multiple values. `clap` will continue parsing values
/// until another argument is reached and it knows `--ui-paths` is done.
///
/// By adding additional parameters to `--ui-paths` we can solve this issue. Consider adding
/// [`Arg::number_of_values(1)`] as discussed above. The following are all valid, and `signer`
/// is parsed as both a subcommand and a value in the second case.
///
/// ```notrust
/// $ program --ui-paths path1 signer
/// $ program --ui-paths path1 --ui-paths signer signer
/// ```
///
/// # Examples
///
/// ```rust
/// # use clap::{App, Arg};
/// Arg::with_name("debug")
/// .short("d")
/// .multiple(true)
/// # ;
/// ```
/// An example with flags
///
/// ```rust
/// # use clap::{App, Arg};
/// let m = App::new("prog")
/// .arg(Arg::with_name("verbose")
/// .multiple(true)
/// .short("v"))
/// .get_matches_from(vec![
/// "prog", "-v", "-v", "-v" // note, -vvv would have same result
/// ]);
///
/// assert!(m.is_present("verbose"));
/// assert_eq!(m.occurrences_of("verbose"), 3);
/// ```
///
/// An example with options
///
/// ```rust
/// # use clap::{App, Arg};
/// let m = App::new("prog")
/// .arg(Arg::with_name("file")
/// .multiple(true)
/// .takes_value(true)
/// .short("F"))
/// .get_matches_from(vec![
/// "prog", "-F", "file1", "file2", "file3"
/// ]);
///
/// assert!(m.is_present("file"));
/// assert_eq!(m.occurrences_of("file"), 1); // notice only one occurrence
/// let files: Vec<_> = m.values_of("file").unwrap().collect();
/// assert_eq!(files, ["file1", "file2", "file3"]);
/// ```
/// This is functionally equivilant to the example above
///
/// ```rust
/// # use clap::{App, Arg};
/// let m = App::new("prog")
/// .arg(Arg::with_name("file")
/// .multiple(true)
/// .takes_value(true)
/// .short("F"))
/// .get_matches_from(vec![
/// "prog", "-F", "file1", "-F", "file2", "-F", "file3"
/// ]);
/// let files: Vec<_> = m.values_of("file").unwrap().collect();
/// assert_eq!(files, ["file1", "file2", "file3"]);
///
/// assert!(m.is_present("file"));
/// assert_eq!(m.occurrences_of("file"), 3); // Notice 3 occurrences
/// let files: Vec<_> = m.values_of("file").unwrap().collect();
/// assert_eq!(files, ["file1", "file2", "file3"]);
/// ```
///
/// A common mistake is to define an option which allows multiples, and a positional argument
///
/// ```rust
/// # use clap::{App, Arg};
/// let m = App::new("prog")
/// .arg(Arg::with_name("file")
/// .multiple(true)
/// .takes_value(true)
/// .short("F"))
/// .arg(Arg::with_name("word")
/// .index(1))
/// .get_matches_from(vec![
/// "prog", "-F", "file1", "file2", "file3", "word"
/// ]);
///
/// assert!(m.is_present("file"));
/// let files: Vec<_> = m.values_of("file").unwrap().collect();
/// assert_eq!(files, ["file1", "file2", "file3", "word"]); // wait...what?!
/// assert!(!m.is_present("word")); // but we clearly used word!
/// ```
/// The problem is clap doesn't know when to stop parsing values for "files". This is further
/// compounded by if we'd said `word -F file1 file2` it would have worked fine, so it would
/// appear to only fail sometimes...not good!
///
/// A solution for the example above is to specify that `-F` only accepts one value, but is
/// allowed to appear multiple times
///
/// ```rust
/// # use clap::{App, Arg};
/// let m = App::new("prog")
/// .arg(Arg::with_name("file")
/// .multiple(true)
/// .takes_value(true)
/// .number_of_values(1)
/// .short("F"))
/// .arg(Arg::with_name("word")
/// .index(1))
/// .get_matches_from(vec![
/// "prog", "-F", "file1", "-F", "file2", "-F", "file3", "word"
/// ]);
///
/// assert!(m.is_present("file"));
/// let files: Vec<_> = m.values_of("file").unwrap().collect();
/// assert_eq!(files, ["file1", "file2", "file3"]);
/// assert!(m.is_present("word"));
/// assert_eq!(m.value_of("word"), Some("word"));
/// ```
/// As a final example, notice if we define [`Arg::number_of_values(1)`] and try to run the
/// problem example above, it would have been a runtime error with a pretty message to the
/// user :)
///
/// ```rust
/// # use clap::{App, Arg, ErrorKind};
/// let res = App::new("prog")
/// .arg(Arg::with_name("file")
/// .multiple(true)
/// .takes_value(true)
/// .number_of_values(1)
/// .short("F"))
/// .arg(Arg::with_name("word")
/// .index(1))
/// .get_matches_from_safe(vec![
/// "prog", "-F", "file1", "file2", "file3", "word"
/// ]);
///
/// assert!(res.is_err());
/// assert_eq!(res.unwrap_err().kind, ErrorKind::UnknownArgument);
/// ```
/// [option]: ./struct.Arg.html#method.takes_value
/// [options]: ./struct.Arg.html#method.takes_value
/// [subcommands]: ./struct.SubCommand.html
/// [positionals]: ./struct.Arg.html#method.index
/// [`Arg::number_of_values(1)`]: ./struct.Arg.html#method.number_of_values
/// [`Arg::multiple(true)`]: ./struct.Arg.html#method.multiple
pub fn multiple(self, multi: bool) -> Self {
if multi {
self.set(ArgSettings::Multiple)
} else {
self.unset(ArgSettings::Multiple)
}
}
/// Specifies a value that *stops* parsing multiple values of a give argument. By default when
/// one sets [`multiple(true)`] on an argument, clap will continue parsing values for that
/// argument until it reaches another valid argument, or one of the other more specific settings
/// for multiple values is used (such as [`min_values`], [`max_values`] or
/// [`number_of_values`]).
///
/// **NOTE:** This setting only applies to [options] and [positional arguments]
///
/// **NOTE:** When the terminator is passed in on the command line, it is **not** stored as one
/// of the values
///
/// # Examples
///
/// ```rust
/// # use clap::{App, Arg};
/// Arg::with_name("vals")
/// .takes_value(true)
/// .multiple(true)
/// .value_terminator(";")
/// # ;
/// ```
/// The following example uses two arguments, a sequence of commands, and the location in which
/// to perform them
///
/// ```rust
/// # use clap::{App, Arg};
/// let m = App::new("prog")
/// .arg(Arg::with_name("cmds")
/// .multiple(true)
/// .allow_hyphen_values(true)
/// .value_terminator(";"))
/// .arg(Arg::with_name("location"))
/// .get_matches_from(vec![
/// "prog", "find", "-type", "f", "-name", "special", ";", "/home/clap"
/// ]);
/// let cmds: Vec<_> = m.values_of("cmds").unwrap().collect();
/// assert_eq!(&cmds, &["find", "-type", "f", "-name", "special"]);
/// assert_eq!(m.value_of("location"), Some("/home/clap"));
/// ```
/// [options]: ./struct.Arg.html#method.takes_value
/// [positional arguments]: ./struct.Arg.html#method.index
/// [`multiple(true)`]: ./struct.Arg.html#method.multiple
/// [`min_values`]: ./struct.Arg.html#method.min_values
/// [`number_of_values`]: ./struct.Arg.html#method.number_of_values
/// [`max_values`]: ./struct.Arg.html#method.max_values
pub fn value_terminator(mut self, term: &'b str) -> Self {
self.setb(ArgSettings::TakesValue);
self.v.terminator = Some(term);
self
}
/// Specifies that an argument can be matched to all child [`SubCommand`]s.
///
/// **NOTE:** Global arguments *only* propagate down, **not** up (to parent commands), however
/// their values once a user uses them will be propagated back up to parents. In effect, this
/// means one should *define* all global arguments at the top level, however it doesn't matter
/// where the user *uses* the global argument.
///
/// # Examples
///
/// ```rust
/// # use clap::{App, Arg};
/// Arg::with_name("debug")
/// .short("d")
/// .global(true)
/// # ;
/// ```
///
/// For example, assume an appliction with two subcommands, and you'd like to define a
/// `--verbose` flag that can be called on any of the subcommands and parent, but you don't
/// want to clutter the source with three duplicate [`Arg`] definitions.
///
/// ```rust
/// # use clap::{App, Arg, SubCommand};
/// let m = App::new("prog")
/// .arg(Arg::with_name("verb")
/// .long("verbose")
/// .short("v")
/// .global(true))
/// .subcommand(SubCommand::with_name("test"))
/// .subcommand(SubCommand::with_name("do-stuff"))
/// .get_matches_from(vec![
/// "prog", "do-stuff", "--verbose"
/// ]);
///
/// assert_eq!(m.subcommand_name(), Some("do-stuff"));
/// let sub_m = m.subcommand_matches("do-stuff").unwrap();
/// assert!(sub_m.is_present("verb"));
/// ```
/// [`SubCommand`]: ./struct.SubCommand.html
/// [required]: ./struct.Arg.html#method.required
/// [`ArgMatches`]: ./struct.ArgMatches.html
/// [`ArgMatches::is_present("flag")`]: ./struct.ArgMatches.html#method.is_present
/// [`Arg`]: ./struct.Arg.html
pub fn global(self, g: bool) -> Self {
if g {
self.set(ArgSettings::Global)
} else {
self.unset(ArgSettings::Global)
}
}
/// Allows an argument to accept explicitly empty values. An empty value must be specified at
/// the command line with an explicit `""`, or `''`
///
/// **NOTE:** Defaults to `true` (Explicitly empty values are allowed)
///
/// **NOTE:** Implicitly sets [`Arg::takes_value(true)`] when set to `false`
///
/// # Examples
///
/// ```rust
/// # use clap::{App, Arg};
/// Arg::with_name("file")
/// .long("file")
/// .empty_values(false)
/// # ;
/// ```
/// The default is to allow empty values, such as `--option ""` would be an empty value. But
/// we can change to make empty values become an error.
///
/// ```rust
/// # use clap::{App, Arg, ErrorKind};
/// let res = App::new("prog")
/// .arg(Arg::with_name("cfg")
/// .long("config")
/// .short("v")
/// .empty_values(false))
/// .get_matches_from_safe(vec![
/// "prog", "--config="
/// ]);
///
/// assert!(res.is_err());
/// assert_eq!(res.unwrap_err().kind, ErrorKind::EmptyValue);
/// ```
/// [`Arg::takes_value(true)`]: ./struct.Arg.html#method.takes_value
pub fn empty_values(mut self, ev: bool) -> Self {
if ev {
self.set(ArgSettings::EmptyValues)
} else {
self = self.set(ArgSettings::TakesValue);
self.unset(ArgSettings::EmptyValues)
}
}
/// Hides an argument from help message output.
///
/// **NOTE:** This does **not** hide the argument from usage strings on error
///
/// # Examples
///
/// ```rust
/// # use clap::{App, Arg};
/// Arg::with_name("debug")
/// .hidden(true)
/// # ;
/// ```
/// Setting `hidden(true)` will hide the argument when displaying help text
///
/// ```rust
/// # use clap::{App, Arg};
/// let m = App::new("prog")
/// .arg(Arg::with_name("cfg")
/// .long("config")
/// .hidden(true)
/// .help("Some help text describing the --config arg"))
/// .get_matches_from(vec![
/// "prog", "--help"
/// ]);
/// ```
///
/// The above example displays
///
/// ```notrust
/// helptest
///
/// USAGE:
/// helptest [FLAGS]
///
/// FLAGS:
/// -h, --help Prints help information
/// -V, --version Prints version information
/// ```
pub fn hidden(self, h: bool) -> Self {
if h {
self.set(ArgSettings::Hidden)
} else {
self.unset(ArgSettings::Hidden)
}
}
/// Specifies a list of possible values for this argument. At runtime, `clap` verifies that
/// only one of the specified values was used, or fails with an error message.
///
/// **NOTE:** This setting only applies to [options] and [positional arguments]
///
/// # Examples
///
/// ```rust
/// # use clap::{App, Arg};
/// Arg::with_name("mode")
/// .takes_value(true)
/// .possible_values(&["fast", "slow", "medium"])
/// # ;
/// ```
///
/// ```rust
/// # use clap::{App, Arg};
/// let m = App::new("prog")
/// .arg(Arg::with_name("mode")
/// .long("mode")
/// .takes_value(true)
/// .possible_values(&["fast", "slow", "medium"]))
/// .get_matches_from(vec![
/// "prog", "--mode", "fast"
/// ]);
/// assert!(m.is_present("mode"));
/// assert_eq!(m.value_of("mode"), Some("fast"));
/// ```
///
/// The next example shows a failed parse from using a value which wasn't defined as one of the
/// possible values.
///
/// ```rust
/// # use clap::{App, Arg, ErrorKind};
/// let res = App::new("prog")
/// .arg(Arg::with_name("mode")
/// .long("mode")
/// .takes_value(true)
/// .possible_values(&["fast", "slow", "medium"]))
/// .get_matches_from_safe(vec![
/// "prog", "--mode", "wrong"
/// ]);
/// assert!(res.is_err());
/// assert_eq!(res.unwrap_err().kind, ErrorKind::InvalidValue);
/// ```
/// [options]: ./struct.Arg.html#method.takes_value
/// [positional arguments]: ./struct.Arg.html#method.index
pub fn possible_values(mut self, names: &[&'b str]) -> Self {
if let Some(ref mut vec) = self.v.possible_vals {
for s in names {
vec.push(s);
}
} else {
self.v.possible_vals = Some(names.iter().map(|s| *s).collect::<Vec<_>>());
}
self
}
/// Specifies a possible value for this argument, one at a time. At runtime, `clap` verifies
/// that only one of the specified values was used, or fails with error message.
///
/// **NOTE:** This setting only applies to [options] and [positional arguments]
///
/// # Examples
///
/// ```rust
/// # use clap::{App, Arg};
/// Arg::with_name("mode")
/// .takes_value(true)
/// .possible_value("fast")
/// .possible_value("slow")
/// .possible_value("medium")
/// # ;
/// ```
///
/// ```rust
/// # use clap::{App, Arg};
/// let m = App::new("prog")
/// .arg(Arg::with_name("mode")
/// .long("mode")
/// .takes_value(true)
/// .possible_value("fast")
/// .possible_value("slow")
/// .possible_value("medium"))
/// .get_matches_from(vec![
/// "prog", "--mode", "fast"
/// ]);
/// assert!(m.is_present("mode"));
/// assert_eq!(m.value_of("mode"), Some("fast"));
/// ```
///
/// The next example shows a failed parse from using a value which wasn't defined as one of the
/// possible values.
///
/// ```rust
/// # use clap::{App, Arg, ErrorKind};
/// let res = App::new("prog")
/// .arg(Arg::with_name("mode")
/// .long("mode")
/// .takes_value(true)
/// .possible_value("fast")
/// .possible_value("slow")
/// .possible_value("medium"))
/// .get_matches_from_safe(vec![
/// "prog", "--mode", "wrong"
/// ]);
/// assert!(res.is_err());
/// assert_eq!(res.unwrap_err().kind, ErrorKind::InvalidValue);
/// ```
/// [options]: ./struct.Arg.html#method.takes_value
/// [positional arguments]: ./struct.Arg.html#method.index
pub fn possible_value(mut self, name: &'b str) -> Self {
if let Some(ref mut vec) = self.v.possible_vals {
vec.push(name);
} else {
self.v.possible_vals = Some(vec![name]);
}
self
}
/// When used with [`Arg::possible_values`] it allows the argument value to pass validation even if
/// the case differs from that of the specified `possible_value`.
///
/// **Pro Tip:** Use this setting with [`arg_enum!`]
///
/// # Examples
///
/// ```rust
/// # use clap::{App, Arg};
/// # use std::ascii::AsciiExt;
/// let m = App::new("pv")
/// .arg(Arg::with_name("option")
/// .long("--option")
/// .takes_value(true)
/// .possible_value("test123")
/// .case_insensitive(true))
/// .get_matches_from(vec![
/// "pv", "--option", "TeSt123",
/// ]);
///
/// assert!(m.value_of("option").unwrap().eq_ignore_ascii_case("test123"));
/// ```
///
/// This setting also works when multiple values can be defined:
///
/// ```rust
/// # use clap::{App, Arg};
/// let m = App::new("pv")
/// .arg(Arg::with_name("option")
/// .short("-o")
/// .long("--option")
/// .takes_value(true)
/// .possible_value("test123")
/// .possible_value("test321")
/// .multiple(true)
/// .case_insensitive(true))
/// .get_matches_from(vec![
/// "pv", "--option", "TeSt123", "teST123", "tESt321"
/// ]);
///
/// let matched_vals = m.values_of("option").unwrap().collect::<Vec<_>>();
/// assert_eq!(&*matched_vals, &["TeSt123", "teST123", "tESt321"]);
/// ```
/// [`Arg::case_insensitive(true)`]: ./struct.Arg.html#method.possible_values
/// [`arg_enum!`]: ./macro.arg_enum.html
pub fn case_insensitive(self, ci: bool) -> Self {
if ci {
self.set(ArgSettings::CaseInsensitive)
} else {
self.unset(ArgSettings::CaseInsensitive)
}
}
/// Specifies the name of the [`ArgGroup`] the argument belongs to.
///
/// # Examples
///
/// ```rust
/// # use clap::{App, Arg};
/// Arg::with_name("debug")
/// .long("debug")
/// .group("mode")
/// # ;
/// ```
///
/// Multiple arguments can be a member of a single group and then the group checked as if it
/// was one of said arguments.
///
/// ```rust
/// # use clap::{App, Arg};
/// let m = App::new("prog")
/// .arg(Arg::with_name("debug")
/// .long("debug")
/// .group("mode"))
/// .arg(Arg::with_name("verbose")
/// .long("verbose")
/// .group("mode"))
/// .get_matches_from(vec![
/// "prog", "--debug"
/// ]);
/// assert!(m.is_present("mode"));
/// ```
/// [`ArgGroup`]: ./struct.ArgGroup.html
pub fn group(mut self, name: &'a str) -> Self {
if let Some(ref mut vec) = self.b.groups {
vec.push(name);
} else {
self.b.groups = Some(vec![name]);
}
self
}
/// Specifies the names of multiple [`ArgGroup`]'s the argument belongs to.
///
/// # Examples
///
/// ```rust
/// # use clap::{App, Arg};
/// Arg::with_name("debug")
/// .long("debug")
/// .groups(&["mode", "verbosity"])
/// # ;
/// ```
///
/// Arguments can be members of multiple groups and then the group checked as if it
/// was one of said arguments.
///
/// ```rust
/// # use clap::{App, Arg};
/// let m = App::new("prog")
/// .arg(Arg::with_name("debug")
/// .long("debug")
/// .groups(&["mode", "verbosity"]))
/// .arg(Arg::with_name("verbose")
/// .long("verbose")
/// .groups(&["mode", "verbosity"]))
/// .get_matches_from(vec![
/// "prog", "--debug"
/// ]);
/// assert!(m.is_present("mode"));
/// assert!(m.is_present("verbosity"));
/// ```
/// [`ArgGroup`]: ./struct.ArgGroup.html
pub fn groups(mut self, names: &[&'a str]) -> Self {
if let Some(ref mut vec) = self.b.groups {
for s in names {
vec.push(s);
}
} else {
self.b.groups = Some(names.into_iter().map(|s| *s).collect::<Vec<_>>());
}
self
}
/// Specifies how many values are required to satisfy this argument. For example, if you had a
/// `-f <file>` argument where you wanted exactly 3 'files' you would set
/// `.number_of_values(3)`, and this argument wouldn't be satisfied unless the user provided
/// 3 and only 3 values.
///
/// **NOTE:** Does *not* require [`Arg::multiple(true)`] to be set. Setting
/// [`Arg::multiple(true)`] would allow `-f <file> <file> <file> -f <file> <file> <file>` where
/// as *not* setting [`Arg::multiple(true)`] would only allow one occurrence of this argument.
///
/// # Examples
///
/// ```rust
/// # use clap::{App, Arg};
/// Arg::with_name("file")
/// .short("f")
/// .number_of_values(3)
/// # ;
/// ```
///
/// Not supplying the correct number of values is an error
///
/// ```rust
/// # use clap::{App, Arg, ErrorKind};
/// let res = App::new("prog")
/// .arg(Arg::with_name("file")
/// .takes_value(true)
/// .number_of_values(2)
/// .short("F"))
/// .get_matches_from_safe(vec![
/// "prog", "-F", "file1"
/// ]);
///
/// assert!(res.is_err());
/// assert_eq!(res.unwrap_err().kind, ErrorKind::WrongNumberOfValues);
/// ```
/// [`Arg::multiple(true)`]: ./struct.Arg.html#method.multiple
pub fn number_of_values(mut self, qty: u64) -> Self {
self.setb(ArgSettings::TakesValue);
self.v.num_vals = Some(qty);
self
}
/// Allows one to perform a custom validation on the argument value. You provide a closure
/// which accepts a [`String`] value, and return a [`Result`] where the [`Err(String)`] is a
/// message displayed to the user.
///
/// **NOTE:** The error message does *not* need to contain the `error:` portion, only the
/// message as all errors will appear as
/// `error: Invalid value for '<arg>': <YOUR MESSAGE>` where `<arg>` is replaced by the actual
/// arg, and `<YOUR MESSAGE>` is the `String` you return as the error.
///
/// **NOTE:** There is a small performance hit for using validators, as they are implemented
/// with [`Rc`] pointers. And the value to be checked will be allocated an extra time in order
/// to to be passed to the closure. This performance hit is extremely minimal in the grand
/// scheme of things.
///
/// # Examples
///
/// ```rust
/// # use clap::{App, Arg};
/// fn has_at(v: String) -> Result<(), String> {
/// if v.contains("@") { return Ok(()); }
/// Err(String::from("The value did not contain the required @ sigil"))
/// }
/// let res = App::new("prog")
/// .arg(Arg::with_name("file")
/// .index(1)
/// .validator(has_at))
/// .get_matches_from_safe(vec![
/// "prog", "some@file"
/// ]);
/// assert!(res.is_ok());
/// assert_eq!(res.unwrap().value_of("file"), Some("some@file"));
/// ```
/// [`String`]: https://doc.rust-lang.org/std/string/struct.String.html
/// [`Result`]: https://doc.rust-lang.org/std/result/enum.Result.html
/// [`Err(String)`]: https://doc.rust-lang.org/std/result/enum.Result.html#variant.Err
/// [`Rc`]: https://doc.rust-lang.org/std/rc/struct.Rc.html
pub fn validator<F>(mut self, f: F) -> Self
where
F: Fn(String) -> Result<(), String> + 'static,
{
self.v.validator = Some(Rc::new(f));
self
}
/// Works identically to Validator but is intended to be used with values that could
/// contain non UTF-8 formatted strings.
///
/// # Examples
///
#[cfg_attr(not(unix), doc = " ```ignore")]
#[cfg_attr(unix, doc = " ```rust")]
/// # use clap::{App, Arg};
/// # use std::ffi::{OsStr, OsString};
/// # use std::os::unix::ffi::OsStrExt;
/// fn has_ampersand(v: &OsStr) -> Result<(), OsString> {
/// if v.as_bytes().iter().any(|b| *b == b'&') { return Ok(()); }
/// Err(OsString::from("The value did not contain the required & sigil"))
/// }
/// let res = App::new("prog")
/// .arg(Arg::with_name("file")
/// .index(1)
/// .validator_os(has_ampersand))
/// .get_matches_from_safe(vec![
/// "prog", "Fish & chips"
/// ]);
/// assert!(res.is_ok());
/// assert_eq!(res.unwrap().value_of("file"), Some("Fish & chips"));
/// ```
/// [`String`]: https://doc.rust-lang.org/std/string/struct.String.html
/// [`OsStr`]: https://doc.rust-lang.org/std/ffi/struct.OsStr.html
/// [`OsString`]: https://doc.rust-lang.org/std/ffi/struct.OsString.html
/// [`Result`]: https://doc.rust-lang.org/std/result/enum.Result.html
/// [`Err(String)`]: https://doc.rust-lang.org/std/result/enum.Result.html#variant.Err
/// [`Rc`]: https://doc.rust-lang.org/std/rc/struct.Rc.html
pub fn validator_os<F>(mut self, f: F) -> Self
where
F: Fn(&OsStr) -> Result<(), OsString> + 'static,
{
self.v.validator_os = Some(Rc::new(f));
self
}
/// Specifies the *maximum* number of values are for this argument. For example, if you had a
/// `-f <file>` argument where you wanted up to 3 'files' you would set `.max_values(3)`, and
/// this argument would be satisfied if the user provided, 1, 2, or 3 values.
///
/// **NOTE:** This does *not* implicitly set [`Arg::multiple(true)`]. This is because
/// `-o val -o val` is multiple occurrences but a single value and `-o val1 val2` is a single
/// occurence with multiple values. For positional arguments this **does** set
/// [`Arg::multiple(true)`] because there is no way to determine the difference between multiple
/// occurences and multiple values.
///
/// # Examples
///
/// ```rust
/// # use clap::{App, Arg};
/// Arg::with_name("file")
/// .short("f")
/// .max_values(3)
/// # ;
/// ```
///
/// Supplying less than the maximum number of values is allowed
///
/// ```rust
/// # use clap::{App, Arg};
/// let res = App::new("prog")
/// .arg(Arg::with_name("file")
/// .takes_value(true)
/// .max_values(3)
/// .short("F"))
/// .get_matches_from_safe(vec![
/// "prog", "-F", "file1", "file2"
/// ]);
///
/// assert!(res.is_ok());
/// let m = res.unwrap();
/// let files: Vec<_> = m.values_of("file").unwrap().collect();
/// assert_eq!(files, ["file1", "file2"]);
/// ```
///
/// Supplying more than the maximum number of values is an error
///
/// ```rust
/// # use clap::{App, Arg, ErrorKind};
/// let res = App::new("prog")
/// .arg(Arg::with_name("file")
/// .takes_value(true)
/// .max_values(2)
/// .short("F"))
/// .get_matches_from_safe(vec![
/// "prog", "-F", "file1", "file2", "file3"
/// ]);
///
/// assert!(res.is_err());
/// assert_eq!(res.unwrap_err().kind, ErrorKind::TooManyValues);
/// ```
/// [`Arg::multiple(true)`]: ./struct.Arg.html#method.multiple
pub fn max_values(mut self, qty: u64) -> Self {
self.setb(ArgSettings::TakesValue);
self.v.max_vals = Some(qty);
self
}
/// Specifies the *minimum* number of values for this argument. For example, if you had a
/// `-f <file>` argument where you wanted at least 2 'files' you would set
/// `.min_values(2)`, and this argument would be satisfied if the user provided, 2 or more
/// values.
///
/// **NOTE:** This does not implicitly set [`Arg::multiple(true)`]. This is because
/// `-o val -o val` is multiple occurrences but a single value and `-o val1 val2` is a single
/// occurence with multiple values. For positional arguments this **does** set
/// [`Arg::multiple(true)`] because there is no way to determine the difference between multiple
/// occurences and multiple values.
///
/// # Examples
///
/// ```rust
/// # use clap::{App, Arg};
/// Arg::with_name("file")
/// .short("f")
/// .min_values(3)
/// # ;
/// ```
///
/// Supplying more than the minimum number of values is allowed
///
/// ```rust
/// # use clap::{App, Arg};
/// let res = App::new("prog")
/// .arg(Arg::with_name("file")
/// .takes_value(true)
/// .min_values(2)
/// .short("F"))
/// .get_matches_from_safe(vec![
/// "prog", "-F", "file1", "file2", "file3"
/// ]);
///
/// assert!(res.is_ok());
/// let m = res.unwrap();
/// let files: Vec<_> = m.values_of("file").unwrap().collect();
/// assert_eq!(files, ["file1", "file2", "file3"]);
/// ```
///
/// Supplying less than the minimum number of values is an error
///
/// ```rust
/// # use clap::{App, Arg, ErrorKind};
/// let res = App::new("prog")
/// .arg(Arg::with_name("file")
/// .takes_value(true)
/// .min_values(2)
/// .short("F"))
/// .get_matches_from_safe(vec![
/// "prog", "-F", "file1"
/// ]);
///
/// assert!(res.is_err());
/// assert_eq!(res.unwrap_err().kind, ErrorKind::TooFewValues);
/// ```
/// [`Arg::multiple(true)`]: ./struct.Arg.html#method.multiple
pub fn min_values(mut self, qty: u64) -> Self {
self.v.min_vals = Some(qty);
self.set(ArgSettings::TakesValue)
}
/// Specifies whether or not an argument should allow grouping of multiple values via a
/// delimiter. I.e. should `--option=val1,val2,val3` be parsed as three values (`val1`, `val2`,
/// and `val3`) or as a single value (`val1,val2,val3`). Defaults to using `,` (comma) as the
/// value delimiter for all arguments that accept values (options and positional arguments)
///
/// **NOTE:** The default is `false`. When set to `true` the default [`Arg::value_delimiter`]
/// is the comma `,`.
///
/// # Examples
///
/// The following example shows the default behavior.
///
/// ```rust
/// # use clap::{App, Arg};
/// let delims = App::new("prog")
/// .arg(Arg::with_name("option")
/// .long("option")
/// .use_delimiter(true)
/// .takes_value(true))
/// .get_matches_from(vec![
/// "prog", "--option=val1,val2,val3",
/// ]);
///
/// assert!(delims.is_present("option"));
/// assert_eq!(delims.occurrences_of("option"), 1);
/// assert_eq!(delims.values_of("option").unwrap().collect::<Vec<_>>(), ["val1", "val2", "val3"]);
/// ```
/// The next example shows the difference when turning delimiters off. This is the default
/// behavior
///
/// ```rust
/// # use clap::{App, Arg};
/// let nodelims = App::new("prog")
/// .arg(Arg::with_name("option")
/// .long("option")
/// .use_delimiter(false)
/// .takes_value(true))
/// .get_matches_from(vec![
/// "prog", "--option=val1,val2,val3",
/// ]);
///
/// assert!(nodelims.is_present("option"));
/// assert_eq!(nodelims.occurrences_of("option"), 1);
/// assert_eq!(nodelims.value_of("option").unwrap(), "val1,val2,val3");
/// ```
/// [`Arg::value_delimiter`]: ./struct.Arg.html#method.value_delimiter
pub fn use_delimiter(mut self, d: bool) -> Self {
if d {
if self.v.val_delim.is_none() {
self.v.val_delim = Some(',');
}
self.setb(ArgSettings::TakesValue);
self.setb(ArgSettings::UseValueDelimiter);
self.unset(ArgSettings::ValueDelimiterNotSet)
} else {
self.v.val_delim = None;
self.unsetb(ArgSettings::UseValueDelimiter);
self.unset(ArgSettings::ValueDelimiterNotSet)
}
}
/// Specifies that *multiple values* may only be set using the delimiter. This means if an
/// if an option is encountered, and no delimiter is found, it automatically assumed that no
/// additional values for that option follow. This is unlike the default, where it is generally
/// assumed that more values will follow regardless of whether or not a delimiter is used.
///
/// **NOTE:** The default is `false`.
///
/// **NOTE:** Setting this to true implies [`Arg::use_delimiter(true)`]
///
/// **NOTE:** It's a good idea to inform the user that use of a delimiter is required, either
/// through help text or other means.
///
/// # Examples
///
/// These examples demonstrate what happens when `require_delimiter(true)` is used. Notice
/// everything works in this first example, as we use a delimiter, as expected.
///
/// ```rust
/// # use clap::{App, Arg};
/// let delims = App::new("prog")
/// .arg(Arg::with_name("opt")
/// .short("o")
/// .takes_value(true)
/// .multiple(true)
/// .require_delimiter(true))
/// .get_matches_from(vec![
/// "prog", "-o", "val1,val2,val3",
/// ]);
///
/// assert!(delims.is_present("opt"));
/// assert_eq!(delims.values_of("opt").unwrap().collect::<Vec<_>>(), ["val1", "val2", "val3"]);
/// ```
/// In this next example, we will *not* use a delimiter. Notice it's now an error.
///
/// ```rust
/// # use clap::{App, Arg, ErrorKind};
/// let res = App::new("prog")
/// .arg(Arg::with_name("opt")
/// .short("o")
/// .takes_value(true)
/// .multiple(true)
/// .require_delimiter(true))
/// .get_matches_from_safe(vec![
/// "prog", "-o", "val1", "val2", "val3",
/// ]);
///
/// assert!(res.is_err());
/// let err = res.unwrap_err();
/// assert_eq!(err.kind, ErrorKind::UnknownArgument);
/// ```
/// What's happening is `-o` is getting `val1`, and because delimiters are required yet none
/// were present, it stops parsing `-o`. At this point it reaches `val2` and because no
/// positional arguments have been defined, it's an error of an unexpected argument.
///
/// In this final example, we contrast the above with `clap`'s default behavior where the above
/// is *not* an error.
///
/// ```rust
/// # use clap::{App, Arg};
/// let delims = App::new("prog")
/// .arg(Arg::with_name("opt")
/// .short("o")
/// .takes_value(true)
/// .multiple(true))
/// .get_matches_from(vec![
/// "prog", "-o", "val1", "val2", "val3",
/// ]);
///
/// assert!(delims.is_present("opt"));
/// assert_eq!(delims.values_of("opt").unwrap().collect::<Vec<_>>(), ["val1", "val2", "val3"]);
/// ```
/// [`Arg::use_delimiter(true)`]: ./struct.Arg.html#method.use_delimiter
pub fn require_delimiter(mut self, d: bool) -> Self {
if d {
self = self.use_delimiter(true);
self.unsetb(ArgSettings::ValueDelimiterNotSet);
self.setb(ArgSettings::UseValueDelimiter);
self.set(ArgSettings::RequireDelimiter)
} else {
self = self.use_delimiter(false);
self.unsetb(ArgSettings::UseValueDelimiter);
self.unset(ArgSettings::RequireDelimiter)
}
}
/// Specifies the separator to use when values are clumped together, defaults to `,` (comma).
///
/// **NOTE:** implicitly sets [`Arg::use_delimiter(true)`]
///
/// **NOTE:** implicitly sets [`Arg::takes_value(true)`]
///
/// # Examples
///
/// ```rust
/// # use clap::{App, Arg};
/// let m = App::new("prog")
/// .arg(Arg::with_name("config")
/// .short("c")
/// .long("config")
/// .value_delimiter(";"))
/// .get_matches_from(vec![
/// "prog", "--config=val1;val2;val3"
/// ]);
///
/// assert_eq!(m.values_of("config").unwrap().collect::<Vec<_>>(), ["val1", "val2", "val3"])
/// ```
/// [`Arg::use_delimiter(true)`]: ./struct.Arg.html#method.use_delimiter
/// [`Arg::takes_value(true)`]: ./struct.Arg.html#method.takes_value
pub fn value_delimiter(mut self, d: &str) -> Self {
self.unsetb(ArgSettings::ValueDelimiterNotSet);
self.setb(ArgSettings::TakesValue);
self.setb(ArgSettings::UseValueDelimiter);
self.v.val_delim = Some(
d.chars()
.nth(0)
.expect("Failed to get value_delimiter from arg"),
);
self
}
/// Specify multiple names for values of option arguments. These names are cosmetic only, used
/// for help and usage strings only. The names are **not** used to access arguments. The values
/// of the arguments are accessed in numeric order (i.e. if you specify two names `one` and
/// `two` `one` will be the first matched value, `two` will be the second).
///
/// This setting can be very helpful when describing the type of input the user should be
/// using, such as `FILE`, `INTERFACE`, etc. Although not required, it's somewhat convention to
/// use all capital letters for the value name.
///
/// **Pro Tip:** It may help to use [`Arg::next_line_help(true)`] if there are long, or
/// multiple value names in order to not throw off the help text alignment of all options.
///
/// **NOTE:** This implicitly sets [`Arg::number_of_values`] if the number of value names is
/// greater than one. I.e. be aware that the number of "names" you set for the values, will be
/// the *exact* number of values required to satisfy this argument
///
/// **NOTE:** implicitly sets [`Arg::takes_value(true)`]
///
/// **NOTE:** Does *not* require or imply [`Arg::multiple(true)`].
///
/// # Examples
///
/// ```rust
/// # use clap::{App, Arg};
/// Arg::with_name("speed")
/// .short("s")
/// .value_names(&["fast", "slow"])
/// # ;
/// ```
///
/// ```rust
/// # use clap::{App, Arg};
/// let m = App::new("prog")
/// .arg(Arg::with_name("io")
/// .long("io-files")
/// .value_names(&["INFILE", "OUTFILE"]))
/// .get_matches_from(vec![
/// "prog", "--help"
/// ]);
/// ```
/// Running the above program produces the following output
///
/// ```notrust
/// valnames
///
/// USAGE:
/// valnames [FLAGS] [OPTIONS]
///
/// FLAGS:
/// -h, --help Prints help information
/// -V, --version Prints version information
///
/// OPTIONS:
/// --io-files <INFILE> <OUTFILE> Some help text
/// ```
/// [`Arg::next_line_help(true)`]: ./struct.Arg.html#method.next_line_help
/// [`Arg::number_of_values`]: ./struct.Arg.html#method.number_of_values
/// [`Arg::takes_value(true)`]: ./struct.Arg.html#method.takes_value
/// [`Arg::multiple(true)`]: ./struct.Arg.html#method.multiple
pub fn value_names(mut self, names: &[&'b str]) -> Self {
self.setb(ArgSettings::TakesValue);
if self.is_set(ArgSettings::ValueDelimiterNotSet) {
self.unsetb(ArgSettings::ValueDelimiterNotSet);
self.setb(ArgSettings::UseValueDelimiter);
}
if let Some(ref mut vals) = self.v.val_names {
let mut l = vals.len();
for s in names {
vals.insert(l, s);
l += 1;
}
} else {
let mut vm = VecMap::new();
for (i, n) in names.iter().enumerate() {
vm.insert(i, *n);
}
self.v.val_names = Some(vm);
}