NAME
Deep::Hash::Exists - Verify existence of keys hash.
SYNOPSIS
use Deep::Hash::Exists ':all';
my $hash_ref = {
        A => 'one',
        B => [ 'one', 'two' ],
        C => { 
            'one' => 1, 
            'two' => 2, 
        },
};
key_exists( $hash_ref, [ 'C', 'one' ] ); # return 1
key_exists( $hash_ref, [ 'D' ] );        # return 0
every_keys( $hash_ref, [ ['A'], ['B', 0], ['C', 'one'] ] ); # return 0
every_keys( $hash_ref, [ ['A'], ['B'], ['C', 'one'] ] );    # return 1
some_keys( $hash_ref, [ ['A'], ['B', 0], ['C', 'one'] ] ); # return 1
some_keys( $hash_ref, [ ['D'], ['B', 0], ['C', 'six'] ] ); # return 0
DESCRIPTION
Exists hash:
my $hash_ref = {
        A => 'one',
        B => [ 'one', 'two' ],
        C => { 
            'one' => 1, 
            'two' => 2, 
        },
};
If verify existence of keys standard way, will be created non existent keys:
exists $hash_ref->{C}{three}{PI}{0};
print Dumper $hash_ref;
Output:
# $VAR1 = {
#          'A' => 'one',
#          'B' => [
#                   'one',
#                   'two'
#                 ]
#          'C' => {
#                   'one' => 1,
#                   'two' => 2,
#                   'three' => {
#                                'PI' => {}
#                              }
#                },
#        };
Subroutine key_exists does not create new keys:
key_exists( $hash_ref, [ 'C', 'three', 'PI', 0 ] );
print Dumper $hash_ref;
Output:
# $VAR1 = {
#          'A' => 'one',
#          'B' => [
#                   'one',
#                   'two'
#                 ],
#          'C' => {
#                   'one' => 1,
#                   'two' => 2
#                 }
#        };
METHODS
The first argument in methods key_exists, every_keys and some_keys can be a hash reference and a blessed hash.
key_exists($$)
key_exists( $hash_ref, $array_ref_keys ) - Verify existence of keys hash.
Return:
If exist keys of hash then return 1, otherwise - 0.
Example:
my $hash_ref = {
        A => 'one',
        B => [ 'one', 'two' ],
        C => { 
            'one' => 1, 
            'two' => 2, 
        },
};
printf "Output: %s", key_exists( $hash_ref, [ 'A' ] );
# Output: 1
printf "Output: %s", key_exists( $hash_ref, [ 'B' ] );
# Output: 1
printf "Output: %s", key_exists( $hash_ref, [ 'B', 0 ] );
# Output: 0
printf "Output: %s", key_exists( $hash_ref, [ 'C', 'one' ] );
# Output: 1
printf "Output: %s", key_exists( $hash_ref, [ 'C', 'three' ] );
# Output: 0
printf "Output: %s", key_exists( $hash_ref, [ 'C', 'three', 'PI', 0 ] );
# Output: 0
# Subroutine does not create new keys.
every_keys($$)
every_keys( $hash_ref, $list_array_ref ) - Verify list of hash keys for existence.
Return:
If exist all keys of hash of the submitted list then return 1, otherwise - 0.
Example:
my $hash_ref = {
        A => 'one',
        B => [ 'one', 'two' ],
        C => { 
            'one' => 1, 
            'two' => 2, 
        },
};
printf "Output: %s", every_keys( $hash_ref, [ ['A'], ['B', 0], ['C', 'one'] ] );
# Output: 0
printf "Output: %s", every_keys( $hash_ref, [ ['A'], ['C', 'one'], ['C', 'two'] ] );
# Output: 1
some_keys($$)
some_keys( $hash_ref, $list_array_ref ) - Verify list of hash keys for existence.
Return:
If exist at least one key of hash of the submitted list then return 1, otherwise - 0.
Example:
my $hash_ref = {
        A => 'one',
        B => [ 'one', 'two' ],
        C => { 
            'one' => 1, 
            'two' => 2, 
        },
};
printf "Output: %s", some_keys( $hash_ref, [ ['A'], ['B', 0], ['C', 'one'] ] );
# Output: 1
printf "Output: %s", some_keys( $hash_ref, [ ['A', 'one'], ['B', 0], ['C', 'three'] ] );
# Output: 0
SEE ALSO
COPYRIGHT AND LICENSE
Copyright (C) 2015 Vitaly Simul <vitalysimul@gmail.com>
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.
AUTHOR
Vitaly Simul <vitalysimul@gmail.com>