felixarntz/values

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## Summary

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This PR can be summarized in the following changelog entry:

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Adresses issue #

## Relevant technical choices
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## Checklist:
- [ ] My code is tested.
- [ ] My code is backward-compatible with PHP 7.0.
- [ ] My code follows the [PSR-2](https://www.php-fig.org/psr/psr-2/) coding standards.
- [ ] My code has proper inline documentation.