NAME

Hash::Slice - Make a hash from a deep slice of another hash

VERSION

Version 0.03

SYNOPSIS

use Hash::Slice qw/slice cslice/;

# A trivial example
my %hash = (a => 1, b => 2, c => 3);

my $slice = slice \%hash, qw/a b/;

# $slice is now { a => 1, b => 2 }


# A hairy example
my %hash = (a => 1, b => 2, c => { d => 3, e => 4 });

my $slice = slice \%hash, qw/a/, [ c => qw/e/ ];

# $slice is now { a => 1, c => { e => 4 } }


# An even hairier example
my %hash = (a => 1, b => 2, c => { d => 3, e => 4, f => { g => 5, h => 6, k => [ 0 .. 4 ] } }, z => 7);

my $slice = slice \%hash, qw/a z/, [ c => qw/e/, [ f => qw/g k/ ] ];

# $slice is now { a => 1, z => 7, c => { e => 4, f => { g => 5, k => [ 0, 1, 2, 3, 4 ] } } }


# Make a cloned-slice of %hash
my %hash = (a => 1, b => 2, c => { d => 3, e => 4, f => { g => 5, h => 6, k => [ 0 .. 4 ] } }, z => 7);

my $slice = cslice \%hash, qw/a z/, [ c => qw/e/, [ f => qw/g k/ ] ];
$slice->{c}->{e} = "red"; # $hash{c}->{e} is still 4

DESCRIPTION

Hash::Slice lets you easily make a deep slice of a hash, specifically a hash containing one or more nested hashes. Instead of just taking a slice of the first level of a hash in an all-or-nothing manner, you can use slice to take a slice of the first level, then take a particular slice of the second level, and so on.

FUNCTIONS

$slice = slice $hash, @cut

%slice = slice $hash, @cut

Make a copy of $hash according to @cut.

For each key in @cut, slice will copy the value of the key over to $slice->{$key}. If $slice encounters an ARRAY instead of a key, it will make a deep slice using the first element of ARRAY as the key and the rest of the array as the cut.

Note, this method will not make an entry in $slice unless the key exists in $hash

Note, unless you are making a deep cut, slice will simply copy the reference of the data being copied, and not make a clone. If you need to make a completely independent copy, use cslice or dcslice.

$slice = cslice $hash, @cut

$slice = clone_slice $hash, @cut

Make a copy of $hash according to @cut. $slice is an independent clone of $hash made using Clone::clone

$slice = dcslice $hash, @cut

$slice = dclone_slice $hash, @cut

Make a copy of $hash according to @cut. $slice is an independent clone of $hash made using Storable::dclone

AUTHOR

Robert Krimen, <rkrimen at cpan.org>

SOURCE

You can contribute or fork this project via GitHub:

http://github.com/robertkrimen/hash-slice/tree/master

git clone git://github.com/robertkrimen/hash-slice.git Hash-Slice

BUGS

Please report any bugs or feature requests to bug-hash-slice at rt.cpan.org, or through the web interface at http://rt.cpan.org/NoAuth/ReportBug.html?Queue=Hash-Slice. 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 Hash::Slice

You can also look for information at:

ACKNOWLEDGEMENTS

COPYRIGHT & LICENSE

Copyright 2007 Robert Krimen, all rights reserved.

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