Defines the DataValue interface and some trivial implementations

wikibase, wikidata, datavalues



Small PHP library that provides interfaces for Value Objects. Several libraries build on top of this foundation.

GitHub Workflow Status codecov

On Packagist: Latest Stable Version Download count


To add this package as a local, per-project dependency to your project, simply add a dependency on data-values/data-values to your project's composer.json file. Here is a minimal example of a composer.json file that just defines a dependency on DataValues 3.x:

        "require": {
            "data-values/data-values": "^3.1.0"

Running the tests

For tests only

composer test

For style checks only

composer cs

For a full CI run

composer ci


DataValues has been written primarily by Jeroen De Dauw, in part for the Wikidata project and Wikimedia Germany.

Contributions where also made by several other awesome people.

Release notes

3.1.0 (2022-10-21)

  • Improved compatibility with PHP 8.1; in particular, the new __serialize/__unserialize methods are implemented now (in addition to the still supported Serializable interface). Care has been taken to keep the output of getHash() stable; if other classes include the PHP serialization of data values in their own hashes, they should instead use the new getSerializationForHash() method where it exists.

3.0.0 (2021-01-19)

  • Removed getCopy from the DataValue interface and all implementations
  • Removed getSortKey from the DataValue interface and all implementations
  • Removed the Comparable, Hashable and Immutable interfaces
  • Removed DATAVALUES_VERSION constant
  • Removed DataValueTest (create a copy if you need it, though better refactor away the bad design)
  • Raised minimum PHP version from 5.5.9 to 7.2

2.3.0 (2019-09-16)

  • composer.json and phpunit.xml.dist are now included in releases

2.2.1 (2019-09-05)

  • Fixed DataValueTest not being part of the release

2.2.0 (2019-09-05)

  • Deprecated DATAVALUES_VERSION constant

2.1.1 (2017-09-28)

  • Fixed DataValueTest not being installable via Composer

2.1.0 (2017-08-09)

  • Removed MediaWiki integration

2.0.0 (2017-08-02)

  • Dropped Copyable interface
  • Dropped deprecated constant DataValues_VERSION, use DATAVALUES_VERSION instead
  • Deprecated newFromArray in all DataValue implementations.
  • Updated minimal required PHP version from 5.3 to 5.5.9
  • Updated documentation throughout the code

1.1.1 (2017-11-02)

  • Add .gitattributes file

1.1.0 (2017-08-09)

  • Remove MediaWiki integration

1.0.0 (2014-09-26)

  • The CI now ensures compatibility with PHP 5.6 and HHVM
  • A lot of type hints where improved
  • Protected methods and fields where changed to private
  • The test bootstrap no longer executes composer update
  • The test bootstrap now sets PHP strict mode
  • The contract of the Hashable::getHash method was updated
  • The MediaWiki internationalization support has been migrated to the JSON based version

0.1.1 (2013-11-22)

  • Removed support for running the tests via the MediaWiki test runner.
  • The test bootstrapping file now automatically does a composer install.
  • Removed custom autoloader in favour of defining autoloading in composer.json.

0.1.0 (2013-11-16)

Initial release with these features:

  • DataValue interface
    • BooleanValue implementation
    • NumberValue implementation
    • StringValue implementation
    • UnDeserializableValue implementation
    • UnknownValue implementation
  • Common interface definitions: Comparable, Copyable, Hashable, Immutable