libregexp-wildcards-perl

NAME
Regexp::Wildcards - Converts wildcard expressions to Perl regular
expressions.

VERSION
Version 1.05

SYNOPSIS
use Regexp::Wildcards;

my $rw = Regexp::Wildcards->new(type => 'unix');

my $re;
$re = $rw->convert('a{b?,c}*'); # Do it Unix shell style.
$re = $rw->convert('a?,b*', 'win32'); # Do it Windows shell style.
$re = $rw->convert('*{x,y}?', 'jokers'); # Process the jokers and
# escape the rest.
$re = $rw->convert('%a_c%', 'sql'); # Turn SQL wildcards into
# regexps.

$rw = Regexp::Wildcards->new(
do => [ qw ], # Do jokers and brackets.
capture => [ qw ], # Capture *'s greedily.
);

$rw->do(add => 'groups'); # Don't escape groups.
$rw->capture(rem => [ qw ]); # Actually we want non-greedy
# matches.
$re = $rw->convert('*a{,(b)?}?c*'); # '(.*?)a(?:|(b).).c(.*?)'
$rw->capture(); # No more captures.

DESCRIPTION
In many situations, users may want to specify patterns to match but
don't need the full power of regexps. Wildcards make one of those sets
of simplified rules. This module converts wildcard expressions to Perl
regular expressions, so that you can use them for matching.

It handles the "*" and "?" jokers, as well as Unix bracketed
alternatives "{,}", but also "%" and "_" SQL wildcards. If required, it
can also keep original "(...)" groups or "^" and "$" anchors. Backspace
("\") is used as an escape character.

Typesets that mimic the behaviour of Windows and Unix shells are also
provided.

METHODS
"new"
my $rw = Regexp::Wildcards->new(do => $what, capture => $capture);
my $rw = Regexp::Wildcards->new(type => $type, capture => $capture);

Constructs a new Regexp::Wildcard object.

"do" lists all features that should be enabled when converting wildcards
to regexps. Refer to "do" for details on what can be passed in $what.

The "type" specifies a predefined set of "do" features to use. See
"type" for details on which types are valid. The "do" option overrides
"type".

"capture" lists which atoms should be capturing. Refer to "capture" for
more details.

"do"
$rw->do($what);
$rw->do(set => $c1);
$rw->do(add => $c2);
$rw->do(rem => $c3);

Specifies the list of metacharacters to convert or to prevent for
escaping. They fit into six classes :

* 'jokers'

Converts "?" to "." and "*" to ".*".

'a**\\*b??\\?c' ==> 'a.*\\*b..\\?c'

* 'sql'

Converts "_" to "." and "%" to ".*".

'a%%\\%b__\\_c' ==> 'a.*\\%b..\\_c'

* 'commas'

Converts all "," to "|" and puts the complete resulting regular
expression inside "(?: ... )".

'a,b{c,d},e' ==> '(?:a|b\\{c|d\\}|e)'

* 'brackets'

Converts all matching "{ ... , ... }" brackets to "(?: ... | ... )"
alternations. If some brackets are unbalanced, it tries to
substitute as many of them as possible, and then escape the
remaining unmatched "{" and "}". Commas outside of any
bracket-delimited block are also escaped.

'a,b{c,d},e' ==> 'a\\,b(?:c|d)\\,e'
'{a\\{b,c}d,e}' ==> '(?:a\\{b|c)d\\,e\\}'
'{a{b,c\\}d,e}' ==> '\\{a\\{b\\,c\\}d\\,e\\}'

* 'groups'

Keeps the parenthesis "( ... )" of the original string without
escaping them. Currently, no check is done to ensure that the
parenthesis are matching.

'a(b(c))d\\(\\)' ==> (no change)

* 'anchors'

Prevents the *beginning-of-line* "^" and *end-of-line* "$" anchors
to be escaped. Since "[...]" character class are currently escaped,
a "^" will always be interpreted as *beginning-of-line*.

'a^b$c' ==> (no change)

Each $c can be any of :

* A hash reference, with wanted metacharacter group names (described
above) as keys and booleans as values ;

* An array reference containing the list of wanted metacharacter
classes ;

* A plain scalar, when only one group is required.

When "set" is present, the classes given as its value replace the
current object options. Then the "add" classes are added, and the "rem"
classes removed.

Passing a sole scalar $what is equivalent as passing "set => $what". No
argument means "set => [ ]".

$rw->do(set => 'jokers'); # Only translate jokers.
$rw->do('jokers'); # Same.
$rw->do(add => [ qw ]); # Translate also SQL and commas.
$rw->do(rem => 'jokers'); # Specifying both 'sql' and
# 'jokers' is useless.
$rw->do(); # Translate nothing.

The "do" method returns the Regexp::Wildcards object.

"type"
$rw->type($type);

Notifies to convert the metacharacters that corresponds to the
predefined type $type. $type can be any of :

* 'jokers', 'sql', 'commas', 'brackets'

Singleton types that enable the corresponding "do" classes.

* 'unix'

Covers typical Unix shell globbing features (effectively 'jokers'
and 'brackets').

* $^O values for common Unix systems

Wrap to 'unix' (see perlport for the list).

* "undef"

Defaults to 'unix'.

* 'win32'

Covers typical Windows shell globbing features (effectively 'jokers'
and 'commas').

* 'dos', 'os2', 'MSWin32', 'cygwin'

Wrap to 'win32'.

In particular, you can usually pass $^O as the $type and get the
corresponding shell behaviour.

$rw->type('win32'); # Set type to win32.
$rw->type($^O); # Set type to unix on Unices and win32 on Windows
$rw->type(); # Set type to unix.

The "type" method returns the Regexp::Wildcards object.

"capture"
$rw->capture($captures);
$rw->capture(set => $c1);
$rw->capture(add => $c2);
$rw->capture(rem => $c3);

Specifies the list of atoms to capture. This method works like "do",
except that the classes are different :

* 'single'

Captures all unescaped *"exactly one"* metacharacters, i.e. "?" for
wildcards or "_" for SQL.

'a???b\\??' ==> 'a(.)(.)(.)b\\?(.)'
'a___b\\__' ==> 'a(.)(.)(.)b\\_(.)'

* 'any'

Captures all unescaped *"any"* metacharacters, i.e. "*" for
wildcards or "%" for SQL.

'a***b\\**' ==> 'a(.*)b\\*(.*)'
'a%%%b\\%%' ==> 'a(.*)b\\%(.*)'

* 'greedy'

When used in conjunction with 'any', it makes the 'any' captures
greedy (by default they are not).

'a***b\\**' ==> 'a(.*?)b\\*(.*?)'
'a%%%b\\%%' ==> 'a(.*?)b\\%(.*?)'

* 'brackets'

Capture matching "{ ... , ... }" alternations.

'a{b\\},\\{c}' ==> 'a(b\\}|\\{c)'

$rw->capture(set => 'single'); # Only capture "exactly one"
# metacharacters.
$rw->capture('single'); # Same.
$rw->capture(add => [ qw ]); # Also greedily capture
# "any" metacharacters.
$rw->capture(rem => 'greedy'); # No more greed please.
$rw->capture(); # Capture nothing.

The "capture" method returns the Regexp::Wildcards object.

"convert"
my $rx = $rw->convert($wc);
my $rx = $rw->convert($wc, $type);

Converts the wildcard expression $wc into a regular expression according
to the options stored into the Regexp::Wildcards object, or to $type if
it's supplied. It successively escapes all unprotected regexp special
characters that doesn't hold any meaning for wildcards, then replace
'jokers', 'sql' and 'commas' or 'brackets' (depending on the "do" or
"type" options), all of this by applying the 'capture' rules specified
in the constructor or by "capture".

EXPORT
An object module shouldn't export any function, and so does this one.

DEPENDENCIES
Carp (core module since perl 5), Scalar::Util, Text::Balanced (since
5.7.3).

CAVEATS
This module does not implement the strange behaviours of Windows shell
that result from the special handling of the three last characters (for
the file extension). For example, Windows XP shell matches *a like
".*a", "*a?" like ".*a.?", "*a??" like ".*a.{0,2}" and so on.

SEE ALSO
Text::Glob.

AUTHOR
Vincent Pit, "", .

You can contact me by mail or on "irc.perl.org" (vincent).

BUGS
Please report any bugs or feature requests to "bug-regexp-wildcards at
rt.cpan.org", or through the web interface at
. I
will be notified, and then you'll automatically be notified of progress
on your bug as I make changes.

SUPPORT
You can find documentation for this module with the perldoc command.

perldoc Regexp::Wildcards

Tests code coverage report is available at
.

COPYRIGHT & LICENSE
Copyright 2007,2008,2009,2013 Vincent Pit, all rights reserved.

This program is free software; you can redistribute it and/or modify it
under the same terms as Perl itself.