NAME

Data::Util - various utility functions

SYNOPSIS

use Data::Util;

my $re = list2re qw/foo bar baz/;
print byval { s/foo/bar/ } $text;
foo(mapval { chomp } @lines);

DESCRIPTION

This module defines a few generally useful utility functions. I got tired of redefining or working around them, so I wrote this module.

Functions

list2re LIST

Converts a list of strings to a regex that matches any of the strings. Especially useful in combination with keys. Example:

my $re = list2re keys %hash;
$str =~ s/($re)/$hash{$1}/g;

byval BLOCK SCALAR

Takes a code block and a value, runs the block with $_ set to that value, and returns the final value of $_. The global value of $_ is not affected. $_ isn't aliased to the input value either, so modifying $_ in the block will not affect the passed in value. Example:

foo(byval { s/!/?/g } $str);
# Calls foo() with the value of $str, but all '!' have been replaced by '?'.
# $str itself is not modified.

mapval BLOCK LIST

Works like a combination of map and byval; i.e. it behaves like map, but $_ is a copy, not aliased to the current element, and the return value is taken from $_ again (it ignores the value returned by the block). Example:

my @foo = mapval { chomp } @bar;
# @foo contains a copy of @bar where all elements have been chomp'd.
# This could also be written as chomp(my @foo = @bar); but that's not
# always possible.

AUTHOR

Lukas Mai, <l.mai at web.de>

COPYRIGHT & LICENSE

Copyright 2009 Lukas Mai.

This program is free software; you can redistribute it and/or modify it under the terms of either: the GNU General Public License as published by the Free Software Foundation; or the Artistic License.

See http://dev.perl.org/licenses/ for more information.