/ 
Struct-Path-0.50
River stage one • 3 direct dependents • 3 total dependents
/ Struct::Path

NAME

Struct::Path - Path for nested structures where path is also a structure

VERSION

Version 0.50

SYNOPSIS

use Struct::Path qw(slist spath spath_delta);

$s = [
    0,
    1,
    {
        '2a' => {
            '2aa' => '2aav',
            '2ab' => '2abv'
        }
    },
    undef
];

@list = slist($s);                              # get all paths and their values
# @list == (
#    [[[0]],0],
#    [[[1]],1],
#    [[[2],{keys => ['2a']},{keys => ['2aa']}],'2aav'],
#    [[[2],{keys => ['2a']},{keys => ['2ab']}],'2abv'],
#    [[[3]],undef]
# )

@r = spath($s, [ [3,0,1] ]);                    # get refs to values by paths
# @r == (\undef, \0, \1)

@r = spath($s, [ [2],{keys => ['2a']},{} ]);    # same, another example
# @r == (\'2aav', \'2abv')

${$r[0]} =~ s/2a/blah-blah-/;                   # replace substructire by path
# $s->[2]{2a}{2aa} eq "blah-blah-av"

@d = spath_delta([[0],[4],[2]], [[0],[1],[3]]); # new steps relatively for first path
# @d == ([1],[3])

EXPORT

Nothing is exported by default.

SUBROUTINES

slist

Returns list of paths and their values from structure.

@list = slist($struct, %opts)

Available options

depth <N>

Don't dive into structure deeper than defined level.

spath

Returns list of references from structure.

@list = spath($struct, $path, %opts)

Addressing method

Path is a list of 'steps', each represents nested level in structure.

Arrayref as a step stands for ARRAY in structure and must contain desired indexes or be empty (means "all items"). Sequence for indexes is important and defines result sequence.

Almost the same for HASHES: step must be a hashref, must contain key keys which value must contain list of desired keys in structure. Empty list means all keys. Sequence in keys list defines result sequence.

Since v0.50 coderefs as steps supported as well. Path as first argument and stack of references (arrayref) as second will be passed to it's input, some true value or undef (if error occur) expected as output.

Why existed *Path* libs ("SEE ALSO") not enough? This scheme has no collisions for paths like '/a/0/c' ('0' may be an ARRAY index or a key for HASH, depends on passed structure). In some cases this is important, for example, when you want to define exact path in structure, but unable to validate it's schema.

See Struct::Path::PerlStyle if you're looking for human friendly path definition method.

Available options

delete <true|false>

Delete specified by path items from structure.

deref <true|false>

Dereference result items.

expand <true|false>

Expand structure if specified in path items does't exists. All newly created items initialized by undef.

strict <true|false>

Croak if at least one element, specified in path, absent in the struct.

spath_delta

Returns delta for two passed paths. By delta means steps from the second path without beginning common steps for both.

@delta = spath_delta($path1, $path2)

LIMITATIONS

No object oriented interface provided.

AUTHOR

Michael Samoglyadov, <mixas at cpan.org>

BUGS

Please report any bugs or feature requests to bug-struct-path at rt.cpan.org, or through the web interface at http://rt.cpan.org/NoAuth/ReportBug.html?Queue=Struct-Path. 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 Struct::Path

You can also look for information at:

SEE ALSO

Data::Diver Data::DPath Data::DRef Data::Focus Data::Hierarchy Data::Nested Data::PathSimple Data::Reach Data::Spath JSON::Path MarpaX::xPathLike Sereal::Path

Struct::Diff Struct::Path::PerlStyle

LICENSE AND COPYRIGHT

Copyright 2016 Michael Samoglyadov.

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.