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//! Definition of a TOML value
use std::collections::{BTreeMap, HashMap};
use std::hash::Hash;
use std::fmt;
use std::ops;
use std::str::FromStr;
use std::vec;
use serde::ser;
use serde::de;
use serde::de::IntoDeserializer;
pub use datetime::{Datetime, DatetimeParseError};
use datetime::{DatetimeFromString, SERDE_STRUCT_FIELD_NAME};
/// Representation of a TOML value.
#[derive(PartialEq, Clone, Debug)]
pub enum Value {
/// Represents a TOML string
String(String),
/// Represents a TOML integer
Integer(i64),
/// Represents a TOML float
Float(f64),
/// Represents a TOML boolean
Boolean(bool),
/// Represents a TOML datetime
Datetime(Datetime),
/// Represents a TOML array
Array(Array),
/// Represents a TOML table
Table(Table),
}
/// Type representing a TOML array, payload of the `Value::Array` variant
pub type Array = Vec<Value>;
/// Type representing a TOML table, payload of the `Value::Table` variant
pub type Table = BTreeMap<String, Value>;
impl Value {
/// Convert a `T` into `toml::Value` which is an enum that can represent
/// any valid TOML data.
///
/// This conversion can fail if `T`'s implementation of `Serialize` decides to
/// fail, or if `T` contains a map with non-string keys.
pub fn try_from<T>(value: T) -> Result<Value, ::ser::Error>
where T: ser::Serialize,
{
value.serialize(Serializer)
}
/// Interpret a `toml::Value` as an instance of type `T`.
///
/// This conversion can fail if the structure of the `Value` does not match the
/// structure expected by `T`, for example if `T` is a struct type but the
/// `Value` contains something other than a TOML table. It can also fail if the
/// structure is correct but `T`'s implementation of `Deserialize` decides that
/// something is wrong with the data, for example required struct fields are
/// missing from the TOML map or some number is too big to fit in the expected
/// primitive type.
pub fn try_into<'de, T>(self) -> Result<T, ::de::Error>
where T: de::Deserialize<'de>,
{
de::Deserialize::deserialize(self)
}
/// Index into a TOML array or map. A string index can be used to access a
/// value in a map, and a usize index can be used to access an element of an
/// array.
///
/// Returns `None` if the type of `self` does not match the type of the
/// index, for example if the index is a string and `self` is an array or a
/// number. Also returns `None` if the given key does not exist in the map
/// or the given index is not within the bounds of the array.
pub fn get<I: Index>(&self, index: I) -> Option<&Value> {
index.index(self)
}
/// Mutably index into a TOML array or map. A string index can be used to
/// access a value in a map, and a usize index can be used to access an
/// element of an array.
///
/// Returns `None` if the type of `self` does not match the type of the
/// index, for example if the index is a string and `self` is an array or a
/// number. Also returns `None` if the given key does not exist in the map
/// or the given index is not within the bounds of the array.
pub fn get_mut<I: Index>(&mut self, index: I) -> Option<&mut Value> {
index.index_mut(self)
}
/// Extracts the integer value if it is an integer.
pub fn as_integer(&self) -> Option<i64> {
match *self { Value::Integer(i) => Some(i), _ => None }
}
/// Tests whether this value is an integer
pub fn is_integer(&self) -> bool {
self.as_integer().is_some()
}
/// Extracts the float value if it is a float.
pub fn as_float(&self) -> Option<f64> {
match *self { Value::Float(f) => Some(f), _ => None }
}
/// Tests whether this value is a float
pub fn is_float(&self) -> bool {
self.as_float().is_some()
}
/// Extracts the boolean value if it is a boolean.
pub fn as_bool(&self) -> Option<bool> {
match *self { Value::Boolean(b) => Some(b), _ => None }
}
/// Tests whether this value is a boolean
pub fn is_bool(&self) -> bool {
self.as_bool().is_some()
}
/// Extracts the string of this value if it is a string.
pub fn as_str(&self) -> Option<&str> {
match *self { Value::String(ref s) => Some(&**s), _ => None }
}
/// Tests if this value is a string
pub fn is_str(&self) -> bool {
self.as_str().is_some()
}
/// Extracts the datetime value if it is a datetime.
///
/// Note that a parsed TOML value will only contain ISO 8601 dates. An
/// example date is:
///
/// ```notrust
/// 1979-05-27T07:32:00Z
/// ```
pub fn as_datetime(&self) -> Option<&Datetime> {
match *self { Value::Datetime(ref s) => Some(s), _ => None }
}
/// Tests whether this value is a datetime
pub fn is_datetime(&self) -> bool {
self.as_datetime().is_some()
}
/// Extracts the array value if it is an array.
pub fn as_array(&self) -> Option<&Vec<Value>> {
match *self { Value::Array(ref s) => Some(s), _ => None }
}
/// Extracts the array value if it is an array.
pub fn as_array_mut(&mut self) -> Option<&mut Vec<Value>> {
match *self { Value::Array(ref mut s) => Some(s), _ => None }
}
/// Tests whether this value is an array
pub fn is_array(&self) -> bool {
self.as_array().is_some()
}
/// Extracts the table value if it is a table.
pub fn as_table(&self) -> Option<&Table> {
match *self { Value::Table(ref s) => Some(s), _ => None }
}
/// Extracts the table value if it is a table.
pub fn as_table_mut(&mut self) -> Option<&mut Table> {
match *self { Value::Table(ref mut s) => Some(s), _ => None }
}
/// Extracts the table value if it is a table.
pub fn is_table(&self) -> bool {
self.as_table().is_some()
}
/// Tests whether this and another value have the same type.
pub fn same_type(&self, other: &Value) -> bool {
match (self, other) {
(&Value::String(..), &Value::String(..)) |
(&Value::Integer(..), &Value::Integer(..)) |
(&Value::Float(..), &Value::Float(..)) |
(&Value::Boolean(..), &Value::Boolean(..)) |
(&Value::Datetime(..), &Value::Datetime(..)) |
(&Value::Array(..), &Value::Array(..)) |
(&Value::Table(..), &Value::Table(..)) => true,
_ => false,
}
}
/// Returns a human-readable representation of the type of this value.
pub fn type_str(&self) -> &'static str {
match *self {
Value::String(..) => "string",
Value::Integer(..) => "integer",
Value::Float(..) => "float",
Value::Boolean(..) => "boolean",
Value::Datetime(..) => "datetime",
Value::Array(..) => "array",
Value::Table(..) => "table",
}
}
}
impl<I> ops::Index<I> for Value where I: Index {
type Output = Value;
fn index(&self, index: I) -> &Value {
self.get(index).expect("index not found")
}
}
impl<I> ops::IndexMut<I> for Value where I: Index {
fn index_mut(&mut self, index: I) -> &mut Value {
self.get_mut(index).expect("index not found")
}
}
impl<'a> From<&'a str> for Value {
#[inline]
fn from(val: &'a str) -> Value {
Value::String(val.to_string())
}
}
impl<V: Into<Value>> From<Vec<V>> for Value {
fn from(val: Vec<V>) -> Value {
Value::Array(val.into_iter().map(|v| v.into()).collect())
}
}
impl<S: Into<String>, V: Into<Value>> From<BTreeMap<S, V>> for Value {
fn from(val: BTreeMap<S, V>) -> Value {
let table = val.into_iter()
.map(|(s, v)| (s.into(), v.into()))
.collect();
Value::Table(table)
}
}
impl<S: Into<String> + Hash + Eq, V: Into<Value>> From<HashMap<S, V>> for Value {
fn from(val: HashMap<S, V>) -> Value {
let table = val.into_iter()
.map(|(s, v)| (s.into(), v.into()))
.collect();
Value::Table(table)
}
}
macro_rules! impl_into_value {
($variant:ident : $T:ty) => {
impl From<$T> for Value {
#[inline]
fn from(val: $T) -> Value {
Value::$variant(val.into())
}
}
}
}
impl_into_value!(String: String);
impl_into_value!(Integer: i64);
impl_into_value!(Integer: i32);
impl_into_value!(Integer: i8);
impl_into_value!(Integer: u8);
impl_into_value!(Integer: u32);
impl_into_value!(Float: f64);
impl_into_value!(Float: f32);
impl_into_value!(Boolean: bool);
impl_into_value!(Datetime: Datetime);
/// Types that can be used to index a `toml::Value`
///
/// Currently this is implemented for `usize` to index arrays and `str` to index
/// tables.
///
/// This trait is sealed and not intended for implementation outside of the
/// `toml` crate.
pub trait Index: Sealed {
#[doc(hidden)]
fn index<'a>(&self, val: &'a Value) -> Option<&'a Value>;
#[doc(hidden)]
fn index_mut<'a>(&self, val: &'a mut Value) -> Option<&'a mut Value>;
}
/// An implementation detail that should not be implemented, this will change in
/// the future and break code otherwise.
#[doc(hidden)]
pub trait Sealed {}
impl Sealed for usize {}
impl Sealed for str {}
impl Sealed for String {}
impl<'a, T: Sealed + ?Sized> Sealed for &'a T {}
impl Index for usize {
fn index<'a>(&self, val: &'a Value) -> Option<&'a Value> {
match *val {
Value::Array(ref a) => a.get(*self),
_ => None,
}
}
fn index_mut<'a>(&self, val: &'a mut Value) -> Option<&'a mut Value> {
match *val {
Value::Array(ref mut a) => a.get_mut(*self),
_ => None,
}
}
}
impl Index for str {
fn index<'a>(&self, val: &'a Value) -> Option<&'a Value> {
match *val {
Value::Table(ref a) => a.get(self),
_ => None,
}
}
fn index_mut<'a>(&self, val: &'a mut Value) -> Option<&'a mut Value> {
match *val {
Value::Table(ref mut a) => a.get_mut(self),
_ => None,
}
}
}
impl Index for String {
fn index<'a>(&self, val: &'a Value) -> Option<&'a Value> {
self[..].index(val)
}
fn index_mut<'a>(&self, val: &'a mut Value) -> Option<&'a mut Value> {
self[..].index_mut(val)
}
}
impl<'s, T: ?Sized> Index for &'s T where T: Index {
fn index<'a>(&self, val: &'a Value) -> Option<&'a Value> {
(**self).index(val)
}
fn index_mut<'a>(&self, val: &'a mut Value) -> Option<&'a mut Value> {
(**self).index_mut(val)
}
}
impl fmt::Display for Value {
fn fmt(&self, f: &mut fmt::Formatter) -> fmt::Result {
::ser::to_string(self).expect("Unable to represent value as string").fmt(f)
}
}
impl FromStr for Value {
type Err = ::de::Error;
fn from_str(s: &str) -> Result<Value, Self::Err> {
::from_str(s)
}
}
impl ser::Serialize for Value {
fn serialize<S>(&self, serializer: S) -> Result<S::Ok, S::Error>
where S: ser::Serializer
{
use serde::ser::SerializeMap;
match *self {
Value::String(ref s) => serializer.serialize_str(s),
Value::Integer(i) => serializer.serialize_i64(i),
Value::Float(f) => serializer.serialize_f64(f),
Value::Boolean(b) => serializer.serialize_bool(b),
Value::Datetime(ref s) => s.serialize(serializer),
Value::Array(ref a) => a.serialize(serializer),
Value::Table(ref t) => {
let mut map = serializer.serialize_map(Some(t.len()))?;
// Be sure to visit non-tables first (and also non
// array-of-tables) as all keys must be emitted first.
for (k, v) in t {
if !v.is_table() && !v.is_array() ||
(v.as_array().map(|a| !a.iter().any(|v| v.is_table())).unwrap_or(false)) {
map.serialize_entry(k, v)?;
}
}
for (k, v) in t {
if v.as_array().map(|a| a.iter().any(|v| v.is_table())).unwrap_or(false) {
map.serialize_entry(k, v)?;
}
}
for (k, v) in t {
if v.is_table() {
map.serialize_entry(k, v)?;
}
}
map.end()
}
}
}
}
impl<'de> de::Deserialize<'de> for Value {
fn deserialize<D>(deserializer: D) -> Result<Value, D::Error>
where D: de::Deserializer<'de>,
{
struct ValueVisitor;
impl<'de> de::Visitor<'de> for ValueVisitor {
type Value = Value;
fn expecting(&self, formatter: &mut fmt::Formatter) -> fmt::Result {
formatter.write_str("any valid TOML value")
}
fn visit_bool<E>(self, value: bool) -> Result<Value, E> {
Ok(Value::Boolean(value))
}
fn visit_i64<E>(self, value: i64) -> Result<Value, E> {
Ok(Value::Integer(value))
}
fn visit_f64<E>(self, value: f64) -> Result<Value, E> {
Ok(Value::Float(value))
}
fn visit_str<E>(self, value: &str) -> Result<Value, E> {
Ok(Value::String(value.into()))
}
fn visit_string<E>(self, value: String) -> Result<Value, E> {
Ok(Value::String(value))
}
fn visit_some<D>(self, deserializer: D) -> Result<Value, D::Error>
where D: de::Deserializer<'de>,
{
de::Deserialize::deserialize(deserializer)
}
fn visit_seq<V>(self, mut visitor: V) -> Result<Value, V::Error>
where V: de::SeqAccess<'de>,
{
let mut vec = Vec::new();
while let Some(elem) = try!(visitor.next_element()) {
vec.push(elem);
}
Ok(Value::Array(vec))
}
fn visit_map<V>(self, mut visitor: V) -> Result<Value, V::Error>
where V: de::MapAccess<'de>,
{
let mut key = String::new();
let datetime = visitor.next_key_seed(DatetimeOrTable {
key: &mut key,
})?;
match datetime {
Some(true) => {
let date: DatetimeFromString = visitor.next_value()?;
return Ok(Value::Datetime(date.value))
}
None => return Ok(Value::Table(BTreeMap::new())),
Some(false) => {}
}
let mut map = BTreeMap::new();
map.insert(key, visitor.next_value()?);
while let Some(key) = visitor.next_key()? {
if map.contains_key(&key) {
let msg = format!("duplicate key: `{}`", key);
return Err(de::Error::custom(msg))
}
map.insert(key, visitor.next_value()?);
}
Ok(Value::Table(map))
}
}
deserializer.deserialize_any(ValueVisitor)
}
}
impl<'de> de::Deserializer<'de> for Value {
type Error = ::de::Error;
fn deserialize_any<V>(self, visitor: V) -> Result<V::Value, ::de::Error>
where V: de::Visitor<'de>,
{
match self {
Value::Boolean(v) => visitor.visit_bool(v),
Value::Integer(n) => visitor.visit_i64(n),
Value::Float(n) => visitor.visit_f64(n),
Value::String(v) => visitor.visit_string(v),
Value::Datetime(v) => visitor.visit_string(v.to_string()),
Value::Array(v) => {
let len = v.len();
let mut deserializer = SeqDeserializer::new(v);
let seq = visitor.visit_seq(&mut deserializer)?;
let remaining = deserializer.iter.len();
if remaining == 0 {
Ok(seq)
} else {
Err(de::Error::invalid_length(len, &"fewer elements in array"))
}
}
Value::Table(v) => {
let len = v.len();
let mut deserializer = MapDeserializer::new(v);
let map = visitor.visit_map(&mut deserializer)?;
let remaining = deserializer.iter.len();
if remaining == 0 {
Ok(map)
} else {
Err(de::Error::invalid_length(len, &"fewer elements in map"))
}
}
}
}
#[inline]
fn deserialize_enum<V>(
self,
_name: &str,
_variants: &'static [&'static str],
visitor: V,
) -> Result<V::Value, ::de::Error>
where
V: de::Visitor<'de>,
{
match self {
Value::String(variant) => visitor.visit_enum(variant.into_deserializer()),
_ => Err(de::Error::invalid_type(de::Unexpected::UnitVariant, &"string only")),
}
}
// `None` is interpreted as a missing field so be sure to implement `Some`
// as a present field.
fn deserialize_option<V>(self, visitor: V) -> Result<V::Value, ::de::Error>
where V: de::Visitor<'de>,
{
visitor.visit_some(self)
}
fn deserialize_newtype_struct<V>(
self,
_name: &'static str,
visitor: V
) -> Result<V::Value, ::de::Error>
where V: de::Visitor<'de>
{
visitor.visit_newtype_struct(self)
}
forward_to_deserialize_any! {
bool u8 u16 u32 u64 i8 i16 i32 i64 f32 f64 char str string unit seq
bytes byte_buf map unit_struct tuple_struct struct
tuple ignored_any identifier
}
}
struct SeqDeserializer {
iter: vec::IntoIter<Value>,
}
impl SeqDeserializer {
fn new(vec: Vec<Value>) -> Self {
SeqDeserializer {
iter: vec.into_iter(),
}
}
}
impl<'de> de::SeqAccess<'de> for SeqDeserializer {
type Error = ::de::Error;
fn next_element_seed<T>(&mut self, seed: T)
-> Result<Option<T::Value>, ::de::Error>
where T: de::DeserializeSeed<'de>,
{
match self.iter.next() {
Some(value) => seed.deserialize(value).map(Some),
None => Ok(None),
}
}
fn size_hint(&self) -> Option<usize> {
match self.iter.size_hint() {
(lower, Some(upper)) if lower == upper => Some(upper),
_ => None,
}
}
}
struct MapDeserializer {
iter: <BTreeMap<String, Value> as IntoIterator>::IntoIter,
value: Option<(String, Value)>,
}
impl MapDeserializer {
fn new(map: BTreeMap<String, Value>) -> Self {
MapDeserializer {
iter: map.into_iter(),
value: None,
}
}
}
impl<'de> de::MapAccess<'de> for MapDeserializer {
type Error = ::de::Error;
fn next_key_seed<T>(&mut self, seed: T) -> Result<Option<T::Value>, ::de::Error>
where T: de::DeserializeSeed<'de>,
{
match self.iter.next() {
Some((key, value)) => {
self.value = Some((key.clone(), value));
seed.deserialize(Value::String(key)).map(Some)
}
None => Ok(None),
}
}
fn next_value_seed<T>(&mut self, seed: T) -> Result<T::Value, ::de::Error>
where T: de::DeserializeSeed<'de>,
{
let (key, res) = match self.value.take() {
Some((key, value)) => (key, seed.deserialize(value)),
None => return Err(de::Error::custom("value is missing")),
};
res.map_err(|mut error| {
error.add_key_context(&key);
error
})
}
fn size_hint(&self) -> Option<usize> {
match self.iter.size_hint() {
(lower, Some(upper)) if lower == upper => Some(upper),
_ => None,
}
}
}
impl<'de> de::IntoDeserializer<'de, ::de::Error> for Value {
type Deserializer = Self;
fn into_deserializer(self) -> Self {
self
}
}
struct Serializer;
impl ser::Serializer for Serializer {
type Ok = Value;
type Error = ::ser::Error;
type SerializeSeq = SerializeVec;
type SerializeTuple = ser::Impossible<Value, ::ser::Error>;
type SerializeTupleStruct = ser::Impossible<Value, ::ser::Error>;
type SerializeTupleVariant = ser::Impossible<Value, ::ser::Error>;
type SerializeMap = SerializeMap;
type SerializeStruct = SerializeMap;
type SerializeStructVariant = ser::Impossible<Value, ::ser::Error>;
fn serialize_bool(self, value: bool) -> Result<Value, ::ser::Error> {
Ok(Value::Boolean(value))
}
fn serialize_i8(self, value: i8) -> Result<Value, ::ser::Error> {
self.serialize_i64(value.into())
}
fn serialize_i16(self, value: i16) -> Result<Value, ::ser::Error> {
self.serialize_i64(value.into())
}
fn serialize_i32(self, value: i32) -> Result<Value, ::ser::Error> {
self.serialize_i64(value.into())
}
fn serialize_i64(self, value: i64) -> Result<Value, ::ser::Error> {
Ok(Value::Integer(value.into()))
}
fn serialize_u8(self, value: u8) -> Result<Value, ::ser::Error> {
self.serialize_i64(value.into())
}
fn serialize_u16(self, value: u16) -> Result<Value, ::ser::Error> {
self.serialize_i64(value.into())
}
fn serialize_u32(self, value: u32) -> Result<Value, ::ser::Error> {
self.serialize_i64(value.into())
}
fn serialize_u64(self, value: u64) -> Result<Value, ::ser::Error> {
if value <= i64::max_value() as u64 {
self.serialize_i64(value as i64)
} else {
Err(ser::Error::custom("u64 value was too large"))
}
}
fn serialize_f32(self, value: f32) -> Result<Value, ::ser::Error> {
self.serialize_f64(value.into())
}
fn serialize_f64(self, value: f64) -> Result<Value, ::ser::Error> {
Ok(Value::Float(value))
}
fn serialize_char(self, value: char) -> Result<Value, ::ser::Error> {
let mut s = String::new();
s.push(value);
self.serialize_str(&s)
}
fn serialize_str(self, value: &str) -> Result<Value, ::ser::Error> {
Ok(Value::String(value.to_owned()))
}
fn serialize_bytes(self, value: &[u8]) -> Result<Value, ::ser::Error> {
let vec = value.iter().map(|&b| Value::Integer(b.into())).collect();
Ok(Value::Array(vec))
}
fn serialize_unit(self) -> Result<Value, ::ser::Error> {
Err(::ser::Error::UnsupportedType)
}
fn serialize_unit_struct(self, _name: &'static str)
-> Result<Value, ::ser::Error> {
Err(::ser::Error::UnsupportedType)
}
fn serialize_unit_variant(self,
_name: &'static str,
_variant_index: u32,
_variant: &'static str)
-> Result<Value, ::ser::Error> {
self.serialize_str(_variant)
}
fn serialize_newtype_struct<T: ?Sized>(self,
_name: &'static str,
value: &T)
-> Result<Value, ::ser::Error>
where T: ser::Serialize,
{
value.serialize(self)
}
fn serialize_newtype_variant<T: ?Sized>(self,
_name: &'static str,
_variant_index: u32,
_variant: &'static str,
_value: &T)
-> Result<Value, ::ser::Error>
where T: ser::Serialize,
{
Err(::ser::Error::UnsupportedType)
}
fn serialize_none(self) -> Result<Value, ::ser::Error> {
Err(::ser::Error::UnsupportedNone)
}
fn serialize_some<T: ?Sized>(self, value: &T) -> Result<Value, ::ser::Error>
where T: ser::Serialize,
{
value.serialize(self)
}
fn serialize_seq(self, len: Option<usize>)
-> Result<Self::SerializeSeq, ::ser::Error>
{
Ok(SerializeVec {
vec: Vec::with_capacity(len.unwrap_or(0))
})
}
fn serialize_tuple(self, _len: usize) -> Result<Self::SerializeTuple, ::ser::Error> {
Err(::ser::Error::UnsupportedType)
}
fn serialize_tuple_struct(self, _name: &'static str, _len: usize)
-> Result<Self::SerializeTupleStruct, ::ser::Error> {
Err(::ser::Error::UnsupportedType)
}
fn serialize_tuple_variant(self,
_name: &'static str,
_variant_index: u32,
_variant: &'static str,
_len: usize)
-> Result<Self::SerializeTupleVariant, ::ser::Error>
{
Err(::ser::Error::UnsupportedType)
}
fn serialize_map(self, _len: Option<usize>)
-> Result<Self::SerializeMap, ::ser::Error>
{
Ok(SerializeMap {
map: BTreeMap::new(),
next_key: None,
})
}
fn serialize_struct(self, _name: &'static str, len: usize)
-> Result<Self::SerializeStruct, ::ser::Error> {
self.serialize_map(Some(len))
}
fn serialize_struct_variant(self,
_name: &'static str,
_variant_index: u32,
_variant: &'static str,
_len: usize)
-> Result<Self::SerializeStructVariant, ::ser::Error>
{
Err(::ser::Error::UnsupportedType)
}
}
struct SerializeVec {
vec: Vec<Value>,
}
struct SerializeMap {
map: BTreeMap<String, Value>,
next_key: Option<String>,
}
impl ser::SerializeSeq for SerializeVec {
type Ok = Value;
type Error = ::ser::Error;
fn serialize_element<T: ?Sized>(&mut self, value: &T) -> Result<(), ::ser::Error>
where T: ser::Serialize
{
self.vec.push(Value::try_from(value)?);
Ok(())
}
fn end(self) -> Result<Value, ::ser::Error> {
Ok(Value::Array(self.vec))
}
}
impl ser::SerializeMap for SerializeMap {
type Ok = Value;
type Error = ::ser::Error;
fn serialize_key<T: ?Sized>(&mut self, key: &T) -> Result<(), ::ser::Error>
where T: ser::Serialize
{
match Value::try_from(key)? {
Value::String(s) => self.next_key = Some(s),
_ => return Err(::ser::Error::KeyNotString),
};
Ok(())
}
fn serialize_value<T: ?Sized>(&mut self, value: &T) -> Result<(), ::ser::Error>
where T: ser::Serialize
{
let key = self.next_key.take();
let key = key.expect("serialize_value called before serialize_key");
match Value::try_from(value) {
Ok(value) => { self.map.insert(key, value); }
Err(::ser::Error::UnsupportedNone) => {}
Err(e) => return Err(e),
}
Ok(())
}
fn end(self) -> Result<Value, ::ser::Error> {
Ok(Value::Table(self.map))
}
}
impl ser::SerializeStruct for SerializeMap {
type Ok = Value;
type Error = ::ser::Error;
fn serialize_field<T: ?Sized>(&mut self, key: &'static str, value: &T) -> Result<(), ::ser::Error>
where T: ser::Serialize
{
try!(ser::SerializeMap::serialize_key(self, key));
ser::SerializeMap::serialize_value(self, value)
}
fn end(self) -> Result<Value, ::ser::Error> {
ser::SerializeMap::end(self)
}
}
struct DatetimeOrTable<'a> {
key: &'a mut String,
}
impl<'a, 'de> de::DeserializeSeed<'de> for DatetimeOrTable<'a> {
type Value = bool;
fn deserialize<D>(self, deserializer: D) -> Result<Self::Value, D::Error>
where D: de::Deserializer<'de>
{
deserializer.deserialize_any(self)
}
}
impl<'a, 'de> de::Visitor<'de> for DatetimeOrTable<'a> {
type Value = bool;
fn expecting(&self, formatter: &mut fmt::Formatter) -> fmt::Result {
formatter.write_str("a string key")
}
fn visit_str<E>(self, s: &str) -> Result<bool, E>
where E: de::Error,
{
if s == SERDE_STRUCT_FIELD_NAME {
Ok(true)
} else {
self.key.push_str(s);
Ok(false)
}
}
fn visit_string<E>(self, s: String) -> Result<bool, E>
where E: de::Error,
{
if s == SERDE_STRUCT_FIELD_NAME {
Ok(true)
} else {
*self.key = s;
Ok(false)
}
}
}