Hash::DefHash - Manipulate defhash


This document describes version 0.06 of Hash::DefHash (from Perl distribution Hash-DefHash), released on 2016-07-12.


 use Hash::DefHash; # imports defhash()

 # create a new defhash object, die when hash is invalid defhash
 $dh = Hash::DefHash->new; # creates an empty hash, or ...

 # ... manipulate an existing hash, defhash() is a synonym for
 # Hash::DefHash->new().
 $dh = defhash({foo=>1});

 # return the original hash
 $hash = $dh->hash;

 # list properties
 @prop = $dh->props;

 # list property names, values, and attributes, will return ($prop => $attrs,
 # ...). Property values will be put in $attrs with key "". For example:
 %content = DefHash::Hash->new({p1=>1, "p1.a"=>2, p2=>3})->contents;
 # => (p1 => {""=>1, a=>2}, p2=>3)

 # get property value, will die if property does not exist
 $propval = $dh->prop($prop);

 # like prop(), but will return undef if property does not exist
 $propval = $dh->get_prop($prop);

 # check whether property exists
 say "exists" if $dh->prop_exists($prop);

 # add a new property, will die if property already exists
 $dh->add_prop($prop, $propval);

 # add new property, or set value for existing property
 $oldpropval = $dh->set_prop($prop, $propval);

 # delete property, noop if property already does not exist. set $delattrs to
 # true to delete all property's attributes.
 $oldpropval = $dh->del_prop($prop, $delattrs);

 # delete all properties, set $delattrs to true to delete all properties's
 # attributes too.

 # get property's attributes. to list defhash attributes, set $prop to undef or
 # ""
 %attrs = $dh->attrs($prop);

 # get attribute value, will die if attribute does not exist
 $attrval = $dh->attr($prop, $attr);

 # like attr(), but will return undef if attribute does not exist
 $attrval = $dh->get_attr($prop, $attr);

 # check whether an attribute exists
 @attrs = $dh->attr_exists($prop, $attr);

 # add attribute to a property, will die if attribute already exists
 $dh->add_attr($prop, $attr, $attrval);

 # add attribute to a property, or set value of existing attribute
 $oldatrrval = $dh->set_attr($prop, $attr, $attrval);

 # delete property's attribute, noop if attribute already does not exist
 $oldattrval = $dh->del_attr($prop, $attr, $attrval);

 # delete all attributes of a property

 # get predefined properties
 say $dh->v;            # shortcut for $dh->get_prop('v')
 say $dh->default_lang; # shortcut for $dh->get_prop('default_lang')
 say $dh->name;         # shortcut for $dh->get_prop('name')
 say $dh->summary;      # shortcut for $dh->get_prop('summary')
 say $dh->description;  # shortcut for $dh->get_prop('description')
 say $dh->tags;         # shortcut for $dh->get_prop('tags')

 # get value in alternate languages
 $propval = $dh->get_prop_lang($prop, $lang);

 # get value in all available languages, result is a hash mapping lang => val
 %vals = $dh->get_prop_all_langs($prop);

 # set value for alternative language
 $oldpropval = $dh->set_prop_lang($prop, $lang, $propval);


defhash([ $hash ]) => OBJ

Shortcut for Hash::DefHash->new($hash). As a bonus, can also detect if $hash is already a defhash and returns it immediately instead of wrapping it again. Exported by default.


new([ $hash ],[ %opts ]) => OBJ

Create a new Hash::DefHash object, which is a thin OO skin over the regular Perl hash. If $hash is not specified, a new anonymous hash is created.

Internally, the object contains a reference to the hash. It does not create a copy of the hash or bless the hash directly. Be careful not to assume that the two are the same!

Known options:

  • check => BOOL (default: 1)

    Whether to check that hash is a valid defhash. Will die if hash turns out to contain invalid keys/values.

  • parent => HASH/DEFHASH_OBJ

    Set defhash's parent. Default language (default_lang) will follow parent's if unset in the current hash.































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Source repository is at


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When submitting a bug or request, please include a test-file or a patch to an existing test-file that illustrates the bug or desired feature.


DefHash specification


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This is free software; you can redistribute it and/or modify it under the same terms as the Perl 5 programming language system itself.