NAME
Regexp::Common::comment -- provide regexes for comments.
SYNOPSIS
use Regexp::Common qw /comment/;
while (<>) {
/$RE{comment}{C}/ and print "Contains a C comment\n";
/$RE{comment}{C++}/ and print "Contains a C++ comment\n";
/$RE{comment}{PHP}/ and print "Contains a PHP comment\n";
/$RE{comment}{Java}/ and print "Contains a Java comment\n";
/$RE{comment}{Perl}/ and print "Contains a Perl comment\n";
/$RE{comment}{awk}/ and print "Contains an awk comment\n";
/$RE{comment}{HTML}/ and print "Contains an HTML comment\n";
}
use Regexp::Common qw /comment RE_comment_HTML/;
while (<>) {
$_ =~ RE_comment_HTML() and print "Contains an HTML comment\n";
}DESCRIPTION
Please consult the manual of Regexp::Common for a general description of the works of this interface.
Do not use this module directly, but load it via Regexp::Common.
This modules gives you regular expressions for comments in various languages.
THE LANGUAGES
Below, the comments of each of the languages are described. The patterns are available as $RE{comment}{LANG}, foreach language LANG. Some languages have variants; it's described at the individual languages how to get the patterns for the variants. Unless mentioned otherwise, {-keep} sets $1, $2, $3 and $4 to the entire comment, the opening marker, the content of the comment, and the closing marker (for many languages, the latter is a newline) respectively.
- Ada
-
Comments in Ada start with
--, and last till the end of the line. - Advisor
-
Advisor is a language used by the HP product glance. Comments for this language start with either
#or//, and last till the end of the line. - Advsys
-
Comments for the Advsys language start with
;and last till the end of the line. See also http://www.wurb.com/if/devsys/12. - Alan
-
Alan comments start with
--, and last till the end of the line. See also http://w1.132.telia.com/~u13207378/alan/manual/alanTOC.html. - Algol 60
-
Comments in the Algol 60 language start with the keyword
comment, and end with a;. See http://www.masswerk.at/algol60/report.htm. - Algol 68
-
In Algol 68, comments are either delimited by
#, or by one of the keywordscoorcomment. The keywords should not be part of another word. See http://westein.arb-phys.uni-dortmund.de/~wb/a68s.txt. With{-keep}, only$1will be set, returning the entire comment. - ALPACA
-
The ALPACA language has comments starting with
/*and ending with*/. - awk
-
The awk programming language uses comments that start with
#and end at the end of the line. - B
-
The B language has comments starting with
/*and ending with*/. - BASIC
-
There are various forms of BASIC around. Currently, we only support the variant supported by mvEnterprise, whose pattern is available as
$RE{comment}{BASIC}{mvEnterprise}. Comments in this language start with a!, a*or the keywordREM, and end till the end of the line. See http://www.rainingdata.com/products/beta/docs/mve/50/ReferenceManual/Basic.pdf. - Beatnik
-
The estoric language Beatnik only uses words consisting of letters. Words are scored according to the rules of Scrabble. Words scoring less than 5 points, or 18 points or more are considered comments (although the compiler might mock at you if you score less than 5 points). Regardless whether
{-keep},$1will be set, and set to the entire comment. This pattern requires perl 5.8.0 or newer. - beta-Juliet
-
The beta-Juliet programming language has comments that start with
//and that continue till the end of the line. See also http://www.catseye.mb.ca/esoteric/b-juliet/index.html. - Befunge-98
-
The estoric language Befunge-98 uses comments that start and end with a
;. See http://www.catseye.mb.ca/esoteric/befunge/98/spec98.html. - Brainfuck
-
The minimal language Brainfuck uses only eight characters,
<,>,[,],+,-,.and,. Any other characters are considered comments. With{-keep},$1is set to the entire comment. - C
-
The C language has comments starting with
/*and ending with*/. - C++
-
The C++ language has two forms of comments. Comments that start with
//and last till the end of the line, and comments that start with/*, and end with*/. If{-keep}is used, only$1will be set, and set to the entire comment. - Crystal Report
-
The formula editor in Crystal Reports uses comments that start with
//, and end with the end of the line. - Dylan
-
There are two types of comments in Dylan. They either start with
//, or are nested comments, delimited with/*and*/. Under{-keep}, only$1will be set, returning the entire comment. This pattern requires perl 5.6.0 or newer. - Eiffel
-
Eiffel comments start with
--, and last till the end of the line. - False
-
In False, comments start with
{and end with}. See http://wouter.fov120.com/false/false.txt - FPL
-
The FPL language has two forms of comments. Comments that start with
//and last till the end of the line, and comments that start with/*, and end with*/. If{-keep}is used, only$1will be set, and set to the entire comment. - Forth
-
Comments in Forth start with
\, and end with the end of the line. See also http://docs.sun.com/sb/doc/806-1377-10. - Fortran
-
There are two forms of Fortran. There's free form Fortran, which has comments that start with
!, and end at the end of the line. The pattern for this is given by$RE{Fortran}. Fixed form Fortran, which has been obsoleted, has comments that start withC,cor*in the first column, or with!anywhere, but the sixth column. The pattern for this are given by$RE{Fortran}{fixed}.See also http://www.cray.com/craydoc/manuals/007-3692-005/html-007-3692-005/.
- Funge-98
-
The estoric language Funge-98 uses comments that start and end with a
;. - fvwm2
-
Configuration files for fvwm2 have comments starting with a
#and lasting the rest of the line. - Haifu
-
Haifu, an estoric language using haikus, has comments starting and ending with a
,. See http://www.dangermouse.net/esoteric/haifu.html. - Haskell
-
There are two types of comments in Haskell. They either start with at least two dashes, or are nested comments, delimited with
{-and-}. Under{-keep}, only$1will be set, returning the entire comment. This pattern requires perl 5.6.0 or newer. - HTML
-
In HTML, comments only appear inside a comment declaration. A comment declaration starts with a
<!, and ends with a>. Inside this declaration, we have zero or more comments. Comments starts with--and end with--, and are optionally followed by whitespace. The pattern$RE{comment}{HTML}recognizes those comment declarations (and hence more than a comment). Note that this is not the same as something that starts with<!--and ends with-->, because the following will be matched completely:<!-- First Comment -- --> Second Comment <!-- -- Third Comment -->Do not be fooled by what your favourite browser thinks is an HTML comment.
If
{-keep}is used, the following are returned: - Hugo
-
There are two types of comments in Hugo. They either start with
!(which cannot be followed by a\), or are nested comments, delimited with!\and\!. Under{-keep}, only$1will be set, returning the entire comment. This pattern requires perl 5.6.0 or newer. - ILLGOL
-
The estoric language ILLGOL uses comments starting with NB and lasting till the end of the line. See http://www.catseye.mb.ca/esoteric/illgol/index.html.
- Java
-
The Java language has two forms of comments. Comments that start with
//and last till the end of the line, and comments that start with/*, and end with*/. If{-keep}is used, only$1will be set, and set to the entire comment. =item LaTeXThe documentation language LaTeX uses comments starting with
%and ending at the end of the line. - LPC
-
The LPC language has comments starting with
/*and ending with*/. - LOGO
-
Comments for the language LOGO start with
;, and last till the end of the line. - lua
-
Comments for the lua language start with
--, and last till the end of the line. See also http://www.lua.org/manual/manual.html. - mutt
-
Configuration files for mutt have comments starting with a
#and lasting the rest of the line. - Oberon
-
Comments in Oberon start with
(*and end with*). See http://www.oberon.ethz.ch/oreport.html. - Pascal
-
There are many implementations of Pascal. Some of them are implemented by this module.
$RE{comment}{Pascal}-
This is the pattern that recognizes comments according to the Pascal ISO standard. This standard says that comments start with either
{, or(*, and end with}or*). This means that{*)and(*}are considered to be comments. Many Pascal applications don't allow this. See http://www.pascal-central.com/docs/iso10206.txt $RE{comment}{Alice}-
The Alice Pascal compiler accepts comments that start with
{and end with}. Comments are not allowed to contain newlines. See http://www.templetons.com/brad/alice/language/. $RE{comment}{Pascal}{Delphi},$RE{comment}{Pascal}{Free}and$RE{comment}{Pascal}{GPC}-
The Delphi Pascal, Free Pascal and the Gnu Pascal Compiler implementations of Pascal all have comments that either start with
//and last till the end of the line, are delimited with{and}or are delimited with(*and*). Patterns for those comments are given by$RE{comment}{Pascal}{Delphi},$RE{comment}{Pascal}{Free}and$RE{comment}{Pascal}{GPC}respectively. These patterns only set$1when{-keep}is used, which will then include the entire comment.See http://info.borland.com/techpubs/delphi5/oplg/, http://www.freepascal.org/docs-html/ref/ref.html and http://www.gnu-pascal.de/gpc/.
$RE{comment}{Pascal}{Workshop}-
The Workshop Pascal compiler, from SUN Microsystems, allows comments that are delimited with either
{and}, delimited with(*)and*), delimited with/*, and*/, or starting and ending with a double quote ("). When{-keep}is used, only$1is set, and returns the entire comment.
- PEARL
-
Comments in PEARL start with a
!and last till the end of the line, or start with/*and end with*/. With{-keep},$1will be set to the entire comment. - PHP
-
Comments in PHP start with either
#or//and last till the end of the line, or are delimited by/*and*/. With{-keep},$1will be set to the entire comment. - PL/B
-
In PL/B, comments start with either
.or;, and end with the next newline. See http://www.mmcctech.com/pl-b/plb-0010.htm. - PL/I
-
The PL/I language has comments starting with
/*and ending with*/. - Perl
-
Perl uses comments that start with a
#, and continue till the end of the line. - Portia
-
The Portia programming language has comments that start with
//, and last till the end of the line. - Python
-
Python uses comments that start with a
#, and continue till the end of the line. - Q-BAL
-
Comments in the Q-BAL language start with
`(a backtick), and contine till the end of the line. - REBOL
-
Comments for the REBOL language start with
;and last till the end of the line. - Ruby
-
Comments in Ruby start with
#and last till the end of the time. - Scheme
-
Scheme comments start with
;, and last till the end of the line. See http://schemers.org/. - shell
-
Comments in various shells start with a
#and end at the end of the line. - Shelta
-
The estoric language Shelta uses comments that start and end with a
;. See http://www.catseye.mb.ca/esoteric/shelta/index.html. - slrn
-
Configuration files for slrn have comments starting with a
%and lasting the rest of the line. - Smalltalk
-
Smalltalk uses comments that start and end with a double quote,
". - SMITH
-
Comments in the SMITH language start with
;, and last till the end of the line. - Squeak
-
In the Smalltalk variant Squeak, comments start and end with
". Double quotes can appear inside comments by doubling them. - SQL
-
Standard SQL uses comments starting with two or more dashes, and ending at the end of the line.
MySQL does not follow the standard. Instead, it allows comments that start with a
#or--(that's two dashes and a space) ending with the following newline, and comments starting with/*, and ending with the next;or*/that isn't inside single or double quotes. A pattern for this is returned by$RE{comment}{SQL}{MySQL}. With{-keep}, only$1will be set, and it returns the entire comment. - Tcl
-
In Tcl, comments start with
#and continue till the end of the line. - TeX
-
The documentation language TeX uses comments starting with
%and ending at the end of the line. - troff
-
The document formatting language troff uses comments starting with
\", and continuing till the end of the line. - vi
-
In configuration files for the editor vi, one can use comments starting with
", and ending at the end of the line. - *W
-
In the language *W, comments start with
||, and end with!!. - zonefile
-
Comments in DNS zonefiles start with
;, and continue till the end of the line.
REFERENCES
- [Go 90]
-
Charles F. Goldfarb: The SGML Handbook. Oxford: Oxford University Press. 1990. ISBN 0-19-853737-9. Ch. 10.3, pp 390-391.
HISTORY
$Log: comment.pm,v $
Revision 2.106 2003/03/12 22:25:42 abigail
- More generic setup to define comments for various languages.
- Expanded and redid the documentation for comment.pm.
- Comments for Advisor, Advsys, Alan, Algol 60, Algol 68, B,
BASIC (mvEnterprise), Forth, Fortran (both fixed and free form),
fvwm2, mutt, Oberon, 6 versions of Pascal,
PEARL (one of the at least four...), PL/B, PL/I, slrn, Squeak.
Revision 2.105 2003/03/09 19:04:42 abigail
- More generic setup to define comments for various languages.
- Expanded and redid the documentation for comment.pm.
Now every language has its own paragraph, describing its comment,
and pointers to webpages.
- Comments for Advisor, Advsys, Alan, Algol 60, Algol 68, B, BASIC
(mvEnterprise), Forth, Fortran (both fixed and free form), fvwm2, mutt,
Oberon, 6 versions of Pascal, PEARL (one of the at least four...), PL/B,
PL/I, slrn, Squeak.
Revision 2.104 2003/02/21 14:48:06 abigail
Crystal Reports
Revision 2.103 2003/02/11 09:39:08 abigail
Added
Revision 2.102 2003/02/07 15:23:54 abigail
Lua and FPL
Revision 2.101 2003/02/01 22:55:31 abigail
Changed Copyright years
Revision 2.100 2003/01/21 23:19:40 abigail
The whole world understands RCS/CVS version numbers, that 1.9 is an
older version than 1.10. Except CPAN. Curse the idiot(s) who think
that version numbers are floats (in which universe do floats have
more than one decimal dot?).
Everything is bumped to version 2.100 because CPAN couldn't deal
with the fact one file had version 1.10.
Revision 1.19 2002/11/06 13:51:34 abigail
Minor POD changes.
Revision 1.18 2002/09/18 18:13:01 abigail
Fixes for 5.005
Revision 1.17 2002/09/04 17:04:24 abigail
Q-BAL
Revision 1.16 2002/08/27 16:50:50 abigail
Patterns for Beatnik, Befunge-98, Funge-98 and W*.
Revision 1.15 2002/08/22 17:04:03 abigail
SMITH added
Revision 1.14 2002/08/22 16:41:25 abigail
+ Added function 'id' and 'from_to' with associated data.
+ Added function 'combine' for languages having multiple syntaxes.
+ Added 'Shelta'
Revision 1.13 2002/08/21 16:00:32 abigail
beta-Juliet, Portia, ILLGOL and Brainfuck.
Revision 1.12 2002/08/20 17:40:37 abigail
- Created a 'nested' function (simplified version from
Regexp::Common::balanced).
- Comments that use 'from' to eol or balanced (nested) delimiters
are now generated from a data array.
- Added Hugo and Haifu.
Revision 1.11 2002/08/05 12:16:58 abigail
Fixed 'Regex::' and 'Rexexp::' typos to 'Regexp::'
(Found my Mike Castle).
Revision 1.10 2002/07/31 23:33:16 abigail
Documented that Haskell and Dylan comments need at least 5.6.0.
Revision 1.9 2002/07/31 23:12:29 abigail
Dylan and Haskell comments can be nested, hence version 5.6.0 of Perl
is needed to be able to make a regex matching them.
Revision 1.8 2002/07/31 14:48:16 abigail
Added LOGO (to please petdance)
Revision 1.7 2002/07/31 13:06:41 abigail
Dealt with -keep for Haskell and Dylan.
Revision 1.6 2002/07/31 00:54:00 abigail
Added comments for Haskell, Dylan, Smalltalk and MySQL.
Revision 1.5 2002/07/30 16:38:23 abigail
Added support for the languages: LaTeX, Tcl, TeX and troff.
Revision 1.4 2002/07/26 16:48:12 abigail
Simplied datastructure for the languages that use single line comments.
Revision 1.3 2002/07/26 16:37:20 abigail
Added new languages: Ada, awk, Eiffel, Java, LPC, PHP, Python,
REBOL, Ruby, vi and zonefile.
Revision 1.2 2002/07/25 22:37:44 abigail
Added 'use strict'.
Added 'no_defaults' to 'use Regex::Common' to prevent loaded of all
defaults.
Revision 1.1 2002/07/25 19:56:07 abigail
Modularizing Regexp::Common.SEE ALSO
Regexp::Common for a general description of how to use this interface.
AUTHOR
Damian Conway (damian@conway.org)
MAINTAINANCE
This package is maintained by Abigail (regexp-common@abigail.nl).
BUGS AND IRRITATIONS
Bound to be plenty.
For a start, there are many common regexes missing. Send them in to regexp-common@abigail.nl.
COPYRIGHT
Copyright (c) 2001 - 2003, Damian Conway. All Rights Reserved.
This module is free software. It may be used, redistributed
and/or modified under the terms of the Perl Artistic License
(see http://www.perl.com/perl/misc/Artistic.html)