## Critical User Journey 2: Create a function definition
**Job To Be Done**
When <situation> I want to <job> so I can <expected outcome or motivation>
**Acceptance criteria**
An editor user...
* [ ] Should be able to find the function creation links easily in the Wikifunctions landing page
* [ ] Should be able to name the function with a primary unique label and a set of alternate names to increase the chances of it being found and used by other users
* [ ] Should be able to easily define the necessary fields to create a custom function definition
* [ ] Should be able to define the necessary number of inputs from 1 to n
* [ ] Should be able to define what type each input should be
* [ ] Should be able to define what is the expected type returned by the function
* [ ] Should be able to easily understand what are the minimum necessary details to define a function
* [ ] Should be able to create a function definition in **at least** my own language
* [ ] Should be able to enrich a function definition with labels in more languages
* [ ] Should be able to save my function so that other users can use it or edit it in the future
* [ ] Should be able to save my changes along with a summary message so that users can see and understand its change history
* [ ] If the creation is not successful, should be able to understand what was wrong and how to fix it
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##Completion checklist
//During the review process, edit and check these items to reflect the completion status of this epic//
* **Functionality**
* [ ] Every project (repository) involved in this user story has its separate Phabricator task
* [ ] Every related task should passes its completion checklist
* [ ] The tests for every involved project pass successfully
* [ ] The build process for every involved project passes successfully
* [ ] Coverage for every involved project has improved or stayed the same
* **Design**
* [ ] Was reviewed and approved by the design/UX team
* **Documentation**
* [ ] Has related and updated documentation, E.g.:
* Internal technical changes: internal repository documentation must be updated (README.md, JSDoc, PHPDoc)
* Infrastructure technical changes: technical changes that reflect on environment, infrastructure, endpoints or any other area of interest for technical contributors should be reflected on MediaWiki extension pages.
* Product or model changes: should have related documentation updated in meta
* **Versioning**
* [ ] If changes in submodule packages are involved, every project that uses this submodule has updated submodule version and passes tests and build