cdif - word context diff
Version 4.19.1
cdif [option] file1 file2
cdif [option] [diff-data]
Options:
-c, -Cn context diff -u, -Un unified diff -i ignore case -b ignore space change -w ignore whitespace -t expand tabs --diff=command specify diff command --subdiff=command specify backend diff command --stat show statistical information --colormap=s specify color map --unit=s word, char or mecab (default word) --[no]color color or not (default true) --[no]256 ANSI 256 color mode (default true) --[no]commandcolor color for command line (default true) --[no]markcolor color for diff mark (default true) --[no]textcolor color for normal text (default true) --[no]unknowncolor color for unknown text (default true) --[no]old print old text (default true) --[no]new print new text (default true) --[no]command print diff command line (default true) --[no]unknown print unknown line (default true) --[no]mark print mark or not (default true) --[no]prefix read git --graph output (default true) --prefix-pattern prefix pattern --visible char=? set visible attributes --[no]mecab use mecab tokenizer (default false) --[no]lenience suppress unexpected input warning (default true)
cdif is a post-processor of the Unix diff command. It highlights deleted, changed and added words based on word context (--unit=word by default). If you want to compare text character-by-character, use option --unit=char. Option --unit=mecab tells to use external mecab command as a tokenizer for Japanese text.
If single or no file is specified, cdif reads that file or STDIN as a output from diff command.
Lines those don't look like diff output are simply ignored and printed.
cdif utilizes Perl Getopt::EX module, and reads ~/.cdifrc file if available when starting up. You can define original and default option there. Next line enables --mecab option and add cossed-out effect for deleted words.
option default --mecab --cm DELETE=+X
Modules under App::cdif can be loaded by -M option without prefix. Next command load App::cdif::colors module.
$ cdif -Mcolors
You can also define options in module file. Read `perldoc Getopt::EX::Module` for detail.
Each lines are displayed in different colors. Each text segment has own labels, and color for them can be specified by --colormap option. Read `perldoc Getopt::EX::Colormap` for detail.
Standard module -Mcolors is loaded by default, and define several color maps for light and dark screen. If you want to use CMY colors in dark screen, place next line in your ~/.cdifrc.
option default --dark-cmy
Option --autocolor is defined in default module to call Getopt::EX::termcolor module. It sets --light or --dark option according to the brightness of the terminal screen. You can set preferred color in your ~/.cdifrc like:
option --light --cmy option --dark --dark-cmy
Automatic setting is done by Getopt::EX::termcolor module and it works with macOS Terminal.app and iTerm.app, and other XTerm compatible terminals. This module accept environment variable TERM_BGCOLOR as a terminal background color. For exapmle, use 000 or #000000 for black and 555 or #FFFFFF for white.
000
#000000
555
#FFFFFF
Option --autocolor is set by default, so override it to do nothing to disable.
option --autocolor --nop
cdif always exit with status zero unless error occured.
Almost same as diff command.
Specify the comparing unit. Default is word and compare each line word-by-word. Specify char if you want to compare them character-by-character.
When mecab is given as an unit, mecab command is called as a tokenizer for non-ASCII text. ASCII text is compared word-by-word. External mecab command has to been installed.
Shortcut for --unit=mecab.
Specify the diff command to use.
Specify the backend diff command to get word differences. Accept normal and unified diff format.
If you want to use git diff command, don't forget to set -U0 option.
--subdiff="git diff -U0 --no-index --histogram"
Use ANSI color escape sequence for output.
Basic colormap format is :
FIELD=COLOR
where the FIELD is one from these :
COMMAND Command line OMARK Old mark NMARK New mark OTEXT Old text NTEXT New text OCHANGE Old change part NCHANGE New change part APPEND Appended part DELETE Deleted part VISIBLE Visualized invisible chars
and additional Common and Merged FIELDs for git-diff combined format.
CMARK Common mark CTEXT Common text MMARK Merged mark MTEXT Merged text
You can make multiple fields same color joining them by = :
FIELD1=FIELD2=...=COLOR
Also wildcard can be used for field name :
*CHANGE=BDw
Multiple fields can be specified by repeating options
--cm FILED1=COLOR1 --cm FIELD2=COLOR2 ...
or combined with comma (,) :
--cm FILED1=COLOR1,FIELD2=COLOR2, ...
Color specification is a combination of single uppercase character representing 8 colors :
R Red G Green B Blue C Cyan M Magenta Y Yellow K Black W White
and alternative (usually brighter) colors in lowercase :
r, g, b, c, m, y, k, w
or RGB values and 24 grey levels if using ANSI 256 or full color terminal :
(255,255,255) : 24bit decimal RGB colors #000000 .. #FFFFFF : 24bit hex RGB colors #000 .. #FFF : 12bit hex RGB 4096 colors 000 .. 555 : 6x6x6 RGB 216 colors L00 .. L25 : Black (L00), 24 grey levels, White (L25)
or color names enclosed by angle bracket :
<red> <blue> <green> <cyan> <magenta> <yellow> <aliceblue> <honeydue> <hotpink> <mooccasin> <medium_aqua_marine>
with other special effects :
D Double-struck (boldface) I Italic U Underline S Stand-out (reverse video)
Above color spec is simplified summary so if you want complete information, read Getopt::EX::Colormap.
Defaults are :
COMMAND => "555/222E" OMARK => "CS" NMARK => "MS" OTEXT => "C" NTEXT => "M" OCHANGE => "K/445" NCHANGE => "K/445" DELETE => "K/544" APPEND => "K/544" CMARK => "GS" MMARK => "YS" CTEXT => "G" MTEXT => "Y"
This is equivalent to :
cdif --cm 'COMMAND=555/222E,OMARK=CS,NMARK=MS' \ --cm 'OTEXT=C,NTEXT=M,*CHANGE=BD/445,DELETE=APPEND=RD/544' \ --cm 'CMARK=GS,MMARK=YS,CTEXT=G,MTEXT=Y'
Enable/Disable using color for the corresponding field.
Disable options appropriate to use for sdif's input: --commandcolor, --markcolor and --textcolor.
Print or not old/new text in diff output.
Print or not command lines preceding diff output.
Print or not lines not look like diff output.
Print or not marks at the top of diff output lines. At this point, this option is effective only for unified diff.
Next example produces the output exactly same as new except visual effects.
cdif -U100 --no-mark --no-old --no-command --no-unknown old new
These options are prepared for watchdiff(1) command.
Understand prefix for diff output including git --graph option. True by default.
Specify prefix pattern in regex. Default pattern is:
(?:\| )*(?: )*
This pattern matches git graph style and whitespace indented diff output.
Set visible attribute for specified characters. Visible character is converted to corresponding Unicode symbol character. Default visible: nul, bel, bs, vt, np, cr, esc, del. Default invisible: ht, nl, sp.
NAME CODE Unicode NAME DEFAULT ---- ---- -------------------------------- ------- nul \000 SYMBOL FOR NULL YES bel \007 SYMBOL FOR BELL YES bs \010 SYMBOL FOR BACKSPACE YES ht \011 SYMBOL FOR HORIZONTAL TABULATION NO nl \012 SYMBOL FOR NEWLINE NO vt \013 SYMBOL FOR VERTICAL TABULATION YES np \014 SYMBOL FOR FORM FEED YES cr \015 SYMBOL FOR CARRIAGE RETURN YES esc \033 SYMBOL FOR ESCAPE YES sp \040 SYMBOL FOR SPACE NO del \177 SYMBOL FOR DELETE YES
Multiple characters can be specified at once, by assembling them by comma (,) like --visible ht=1,sp=1; or connecting them by equal sign (=) like --visible ht=sp=1. Character name accept wildcard; --visible '*=1'.
,
--visible ht=1,sp=1
=
--visible ht=sp=1
--visible '*=1'
Colormap label VISIBLE is applied to those characters. Default setting is S, and visible characters are displayed in reverse video. Unlike other colormaps, only special effects can be set to this label. Effect D (double-struck) is exception (See "~" in Getopt::EX::Colormap).
VISIBLE
S
D
Print statistical information at the end of output. It shows number of total appended/deleted/changed words in the context of cdif. It's common to have many insertions and deletions of newlines because of text filling process. So normal information is followed by modified number which ignores insert/delete newlines.
Suppress warning message for unexpected input from diff command. True by default.
See `perldoc App::sdif` how to use related commands under the GIT environment.
Environment variable CDIFOPTS is used to set default options.
Since cdif produces ANSI Erase Line terminal sequence, it is convenient to set less command understand them.
LESS=-cR LESSANSIENDCHARS=mK
Kazumasa Utashiro
Copyright 1992-2021 Kazumasa Utashiro
This library is free software; you can redistribute it and/or modify it under the same terms as Perl itself.
App::sdif, https://github.com/kaz-utashiro/sdif-tools
sdif(1), watchdiff(1)
Getopt::EX::Colormap
https://taku910.github.io/mecab/
cdif is naturally not very fast because it uses normal diff command as a back-end processor to compare words.
To install App::sdif, copy and paste the appropriate command in to your terminal.
cpanm
cpanm App::sdif
CPAN shell
perl -MCPAN -e shell install App::sdif
For more information on module installation, please visit the detailed CPAN module installation guide.