runtime/doc/usr_06.txt - third_party/vim - Git at Google

 *usr_06.txt*	For Vim version 7.0f.  Last change: 2006 Apr 24

 		     VIM USER MANUAL - by Bram Moolenaar

 			  Using syntax highlighting


 Black and white text is boring.  With colors your file comes to life.  This
 not only looks nice, it also speeds up your work.  Change the colors used for
 the different sorts of text.  Print your text, with the colors you see on the
 screen.

 |06.1|	Switching it on
 |06.2|	No or wrong colors?
 |06.3|	Different colors
 |06.4|	With colors or without colors
 |06.5|	Printing with colors
 |06.6|	Further reading

      Next chapter: |usr_07.txt|  Editing more than one file
  Previous chapter: |usr_05.txt|  Set your settings
 Table of contents: |usr_toc.txt|

 ==============================================================================
 *06.1*	Switching it on

 It all starts with one simple command: >

 	:syntax enable

 That should work in most situations to get color in your files.  Vim will
 automagically detect the type of file and load the right syntax highlighting.
 Suddenly comments are blue, keywords brown and strings red.  This makes it
 easy to overview the file.  After a while you will find that black&white text
 slows you down!

 If you always want to use syntax highlighting, put the ":syntax enable"
 command in your |vimrc| file.

 If you want syntax highlighting only when the terminal supports colors, you
 can put this in your |vimrc| file: >

 	if &t_Co > 1
 	   syntax enable
 	endif

 If you want syntax highlighting only in the GUI version, put the ":syntax
 enable" command in your |gvimrc| file.

 ==============================================================================
 *06.2*	No or wrong colors?

 There can be a number of reasons why you don't see colors:

 - Your terminal does not support colors.
 	Vim will use bold, italic and underlined text, but this doesn't look
 	very nice.  You probably will want to try to get a terminal with
 	colors.  For Unix, I recommend the xterm from the XFree86 project:
 	|xfree-xterm|.

 - Your terminal does support colors, but Vim doesn't know this.
 	Make sure your $TERM setting is correct.  For example, when using an
 	xterm that supports colors: >

 		setenv TERM xterm-color
 <
 	or (depending on your shell): >

 		TERM=xterm-color; export TERM

 <	The terminal name must match the terminal you are using.  If it
 	still doesn't work, have a look at |xterm-color|, which shows a few
 	ways to make Vim display colors (not only for an xterm).

 - The file type is not recognized.
 	Vim doesn't know all file types, and sometimes it's near to impossible
 	to tell what language a file uses.  Try this command: >

 		:set filetype
 <
 	If the result is "filetype=" then the problem is indeed that Vim
 	doesn't know what type of file this is.  You can set the type
 	manually: >

 		:set filetype=fortran

 <	To see which types are available, look in the directory
 	$VIMRUNTIME/syntax.  For the GUI you can use the Syntax menu.
 	Setting the filetype can also be done with a |modeline|, so that the
 	file will be highlighted each time you edit it.  For example, this
 	line can be used in a Makefile (put it near the start or end of the
 	file): >

 		# vim: syntax=make

 <	You might know how to detect the file type yourself.  Often the file
 	name extension (after the dot) can be used.
 	See |new-filetype| for how to tell Vim to detect that file type.

 - There is no highlighting for your file type.
 	You could try using a similar file type by manually setting it as
 	mentioned above.  If that isn't good enough, you can write your own
 	syntax file, see |mysyntaxfile|.


 Or the colors could be wrong:

 - The colored text is very hard to read.
 	Vim guesses the background color that you are using.  If it is black
 	(or another dark color) it will use light colors for text.  If it is
 	white (or another light color) it will use dark colors for text.  If
 	Vim guessed wrong the text will be hard to read.  To solve this, set
 	the 'background' option.  For a dark background: >

 		:set background=dark

 <	And for a light background: >

 		:set background=light

 <	Make sure you put this _before_ the ":syntax enable" command,
 	otherwise the colors will already have been set.  You could do
 	":syntax reset" after setting 'background' to make Vim set the default
 	colors again.

 - The colors are wrong when scrolling bottom to top.
 	Vim doesn't read the whole file to parse the text.  It starts parsing
 	wherever you are viewing the file.  That saves a lot of time, but
 	sometimes the colors are wrong.  A simple fix is hitting CTRL-L.  Or
 	scroll back a bit and then forward again.
 	For a real fix, see |:syn-sync|.  Some syntax files have a way to make
 	it look further back, see the help for the specific syntax file.  For
 	example, |tex.vim| for the TeX syntax.

 ==============================================================================
 *06.3*	Different colors				*:syn-default-override*

 If you don't like the default colors, you can select another color scheme.  In
 the GUI use the Edit/Color Scheme menu.  You can also type the command: >

 	:colorscheme evening

 "evening" is the name of the color scheme.  There are several others you might
 want to try out.  Look in the directory $VIMRUNTIME/colors.

 When you found the color scheme that you like, add the ":colorscheme" command
 to your |vimrc| file.

 You could also write your own color scheme.  This is how you do it:

 1. Select a color scheme that comes close.  Copy this file to your own Vim
    directory.  For Unix, this should work: >

 	!mkdir ~/.vim/colors
 	!cp $VIMRUNTIME/colors/morning.vim ~/.vim/colors/mine.vim
 <
    This is done from Vim, because it knows the value of $VIMRUNTIME.

 2. Edit the color scheme file.  These entries are useful:

 	term		attributes in a B&W terminal
 	cterm		attributes in a color terminal
 	ctermfg		foreground color in a color terminal
 	ctermbg		background color in a color terminal
 	gui		attributes in the GUI
 	guifg		foreground color in the GUI
 	guibg		background color in the GUI

    For example, to make comments green: >

 	:highlight Comment ctermfg=green guifg=green
 <
    Attributes you can use for "cterm" and "gui" are "bold" and "underline".
    If you want both, use "bold,underline".  For details see the |:highlight|
    command.

 3. Tell Vim to always use your color scheme.  Put this line in your |vimrc|: >

 	colorscheme mine

 If you want to see what the most often used color combinations look like, use
 this command: >

 	:runtime syntax/colortest.vim

 You will see text in various color combinations.  You can check which ones are
 readable and look nice.

 ==============================================================================
 *06.4*	With colors or without colors

 Displaying text in color takes a lot of effort.  If you find the displaying
 too slow, you might want to disable syntax highlighting for a moment: >

 	:syntax clear

 When editing another file (or the same one) the colors will come back.

 							*:syn-off*
 If you want to stop highlighting completely use: >

 	:syntax off

 This will completely disable syntax highlighting and remove it immediately for
 all buffers.

 							*:syn-manual*
 If you want syntax highlighting only for specific files, use this: >

 	:syntax manual

 This will enable the syntax highlighting, but not switch it on automatically
 when starting to edit a buffer.  To switch highlighting on for the current
 buffer, set the 'syntax' option: >

 	:set syntax=ON
 <
 ==============================================================================
 *06.5*	Printing with colors				*syntax-printing*

 In the MS-Windows version you can print the current file with this command: >

 	:hardcopy

 You will get the usual printer dialog, where you can select the printer and a
 few settings.  If you have a color printer, the paper output should look the
 same as what you see inside Vim.  But when you use a dark background the
 colors will be adjusted to look good on white paper.

 There are several options that change the way Vim prints:
 	'printdevice'
 	'printheader'
 	'printfont'
 	'printoptions'

 To print only a range of lines,  use Visual mode to select the lines and then
 type the command: >

 	v100j:hardcopy

 "v" starts Visual mode.  "100j" moves a hundred lines down, they will be
 highlighted.  Then ":hardcopy" will print those lines.  You can use other
 commands to move in Visual mode, of course.

 This also works on Unix, if you have a PostScript printer.  Otherwise, you
 will have to do a bit more work.  You need to convert the text to HTML first,
 and then print it from a web browser such as Netscape.

 Convert the current file to HTML with this command: >

 	:source $VIMRUNTIME/syntax/2html.vim

 You will see it crunching away, this can take quite a while for a large file.
 Some time later another window shows the HTML code.  Now write this somewhere
 (doesn't matter where, you throw it away later):
 >
 	:write main.c.html

 Open this file in your favorite browser and print it from there.  If all goes
 well, the output should look exactly as it does in Vim.  See |2html.vim| for
 details.  Don't forget to delete the HTML file when you are done with it.

 Instead of printing, you could also put the HTML file on a web server, and let
 others look at the colored text.

 ==============================================================================
 *06.6*	Further reading

 |usr_44.txt|  Your own syntax highlighted.
 |syntax|      All the details.

 ==============================================================================

 Next chapter: |usr_07.txt|  Editing more than one file

 Copyright: see |manual-copyright|  vim:tw=78:ts=8:ft=help:norl:
	usr_06.txt For Vim version 7.0f. Last change: 2006 Apr 24

	VIM USER MANUAL - by Bram Moolenaar

	Using syntax highlighting


	Black and white text is boring. With colors your file comes to life. This
	not only looks nice, it also speeds up your work. Change the colors used for
	the different sorts of text. Print your text, with the colors you see on the
	screen.

	\|06.1\| Switching it on
	\|06.2\| No or wrong colors?
	\|06.3\| Different colors
	\|06.4\| With colors or without colors
	\|06.5\| Printing with colors
	\|06.6\| Further reading

	Next chapter: \|usr_07.txt\| Editing more than one file
	Previous chapter: \|usr_05.txt\| Set your settings
	Table of contents: \|usr_toc.txt\|

	==============================================================================
	06.1 Switching it on

	It all starts with one simple command: >

	:syntax enable

	That should work in most situations to get color in your files. Vim will
	automagically detect the type of file and load the right syntax highlighting.
	Suddenly comments are blue, keywords brown and strings red. This makes it
	easy to overview the file. After a while you will find that black&white text
	slows you down!

	If you always want to use syntax highlighting, put the ":syntax enable"
	command in your \|vimrc\| file.

	If you want syntax highlighting only when the terminal supports colors, you
	can put this in your \|vimrc\| file: >

	if &t_Co > 1
	syntax enable
	endif

	If you want syntax highlighting only in the GUI version, put the ":syntax
	enable" command in your \|gvimrc\| file.

	==============================================================================
	06.2 No or wrong colors?

	There can be a number of reasons why you don't see colors:

	- Your terminal does not support colors.
	Vim will use bold, italic and underlined text, but this doesn't look
	very nice. You probably will want to try to get a terminal with
	colors. For Unix, I recommend the xterm from the XFree86 project:
	\|xfree-xterm\|.

	- Your terminal does support colors, but Vim doesn't know this.
	Make sure your $TERM setting is correct. For example, when using an
	xterm that supports colors: >

	setenv TERM xterm-color
	<
	or (depending on your shell): >

	TERM=xterm-color; export TERM

	< The terminal name must match the terminal you are using. If it
	still doesn't work, have a look at \|xterm-color\|, which shows a few
	ways to make Vim display colors (not only for an xterm).

	- The file type is not recognized.
	Vim doesn't know all file types, and sometimes it's near to impossible
	to tell what language a file uses. Try this command: >

	:set filetype
	<
	If the result is "filetype=" then the problem is indeed that Vim
	doesn't know what type of file this is. You can set the type
	manually: >

	:set filetype=fortran

	< To see which types are available, look in the directory
	$VIMRUNTIME/syntax. For the GUI you can use the Syntax menu.
	Setting the filetype can also be done with a \|modeline\|, so that the
	file will be highlighted each time you edit it. For example, this
	line can be used in a Makefile (put it near the start or end of the
	file): >

	# vim: syntax=make

	< You might know how to detect the file type yourself. Often the file
	name extension (after the dot) can be used.
	See \|new-filetype\| for how to tell Vim to detect that file type.

	- There is no highlighting for your file type.
	You could try using a similar file type by manually setting it as
	mentioned above. If that isn't good enough, you can write your own
	syntax file, see \|mysyntaxfile\|.


	Or the colors could be wrong:

	- The colored text is very hard to read.
	Vim guesses the background color that you are using. If it is black
	(or another dark color) it will use light colors for text. If it is
	white (or another light color) it will use dark colors for text. If
	Vim guessed wrong the text will be hard to read. To solve this, set
	the 'background' option. For a dark background: >

	:set background=dark

	< And for a light background: >

	:set background=light

	< Make sure you put this _before_ the ":syntax enable" command,
	otherwise the colors will already have been set. You could do
	":syntax reset" after setting 'background' to make Vim set the default
	colors again.

	- The colors are wrong when scrolling bottom to top.
	Vim doesn't read the whole file to parse the text. It starts parsing
	wherever you are viewing the file. That saves a lot of time, but
	sometimes the colors are wrong. A simple fix is hitting CTRL-L. Or
	scroll back a bit and then forward again.
	For a real fix, see \|:syn-sync\|. Some syntax files have a way to make
	it look further back, see the help for the specific syntax file. For
	example, \|tex.vim\| for the TeX syntax.

	==============================================================================
	06.3 Different colors :syn-default-override

	If you don't like the default colors, you can select another color scheme. In
	the GUI use the Edit/Color Scheme menu. You can also type the command: >

	:colorscheme evening

	"evening" is the name of the color scheme. There are several others you might
	want to try out. Look in the directory $VIMRUNTIME/colors.

	When you found the color scheme that you like, add the ":colorscheme" command
	to your \|vimrc\| file.

	You could also write your own color scheme. This is how you do it:

	1. Select a color scheme that comes close. Copy this file to your own Vim
	directory. For Unix, this should work: >

	!mkdir ~/.vim/colors
	!cp $VIMRUNTIME/colors/morning.vim ~/.vim/colors/mine.vim
	<
	This is done from Vim, because it knows the value of $VIMRUNTIME.

	2. Edit the color scheme file. These entries are useful:

	term attributes in a B&W terminal
	cterm attributes in a color terminal
	ctermfg foreground color in a color terminal
	ctermbg background color in a color terminal
	gui attributes in the GUI
	guifg foreground color in the GUI
	guibg background color in the GUI

	For example, to make comments green: >

	:highlight Comment ctermfg=green guifg=green
	<
	Attributes you can use for "cterm" and "gui" are "bold" and "underline".
	If you want both, use "bold,underline". For details see the \|:highlight\|
	command.

	3. Tell Vim to always use your color scheme. Put this line in your \|vimrc\|: >

	colorscheme mine

	If you want to see what the most often used color combinations look like, use
	this command: >

	:runtime syntax/colortest.vim

	You will see text in various color combinations. You can check which ones are
	readable and look nice.

	==============================================================================
	06.4 With colors or without colors

	Displaying text in color takes a lot of effort. If you find the displaying
	too slow, you might want to disable syntax highlighting for a moment: >

	:syntax clear

	When editing another file (or the same one) the colors will come back.

	:syn-off
	If you want to stop highlighting completely use: >

	:syntax off

	This will completely disable syntax highlighting and remove it immediately for
	all buffers.

	:syn-manual
	If you want syntax highlighting only for specific files, use this: >

	:syntax manual

	This will enable the syntax highlighting, but not switch it on automatically
	when starting to edit a buffer. To switch highlighting on for the current
	buffer, set the 'syntax' option: >

	:set syntax=ON
	<
	==============================================================================
	06.5 Printing with colors syntax-printing

	In the MS-Windows version you can print the current file with this command: >

	:hardcopy

	You will get the usual printer dialog, where you can select the printer and a
	few settings. If you have a color printer, the paper output should look the
	same as what you see inside Vim. But when you use a dark background the
	colors will be adjusted to look good on white paper.

	There are several options that change the way Vim prints:
	'printdevice'
	'printheader'
	'printfont'
	'printoptions'

	To print only a range of lines, use Visual mode to select the lines and then
	type the command: >

	v100j:hardcopy

	"v" starts Visual mode. "100j" moves a hundred lines down, they will be
	highlighted. Then ":hardcopy" will print those lines. You can use other
	commands to move in Visual mode, of course.

	This also works on Unix, if you have a PostScript printer. Otherwise, you
	will have to do a bit more work. You need to convert the text to HTML first,
	and then print it from a web browser such as Netscape.

	Convert the current file to HTML with this command: >

	:source $VIMRUNTIME/syntax/2html.vim

	You will see it crunching away, this can take quite a while for a large file.
	Some time later another window shows the HTML code. Now write this somewhere
	(doesn't matter where, you throw it away later):
	>
	:write main.c.html

	Open this file in your favorite browser and print it from there. If all goes
	well, the output should look exactly as it does in Vim. See \|2html.vim\| for
	details. Don't forget to delete the HTML file when you are done with it.

	Instead of printing, you could also put the HTML file on a web server, and let
	others look at the colored text.

	==============================================================================
	06.6 Further reading

	\|usr_44.txt\| Your own syntax highlighted.
	\|syntax\| All the details.

	==============================================================================

	Next chapter: \|usr_07.txt\| Editing more than one file

	Copyright: see \|manual-copyright\| vim:tw=78:ts=8:ft=help:norl: