# What is the "compat" admonition in Documenter used for?

**URL:** <https://discourse.julialang.org/t/what-is-the-compat-admonition-in-documenter-used-for/75900>\
**Category:** Tooling\
**Tags:** documenter\
**Created:** [February 6, 2022, 1:52pm UTC](https://discourse.julialang.org/t/what-is-the-compat-admonition-in-documenter-used-for/75900 "2022-02-06T13:52:40Z")\
**Posts on this page:** 3\
**Page:** 1

<div class="post-metadata">

**Author:** ![sylvaticus](https://sea2.discourse-cdn.com/julialang/user_avatar/discourse.julialang.org/sylvaticus/32/203883_2.png) [@sylvaticus](https://discourse.julialang.org/u/sylvaticus)\
**Post date:** [February 6, 2022, 1:52pm UTC](https://discourse.julialang.org/t/what-is-the-compat-admonition-in-documenter-used-for/75900/1 "2022-02-06T13:52:40Z")

</div>

Sorry to be dumb, but what “compat” means in “Compat admonition” in Documenter ?  
And now that I am trying to post… what’s the relation with the “compat” session in Project.toml ?

 ![image](https://global.discourse-cdn.com/julialang/original/3X/2/9/2997e214fa206f8990c10c1f2ae2cea25368f639.png)

![image](https://global.discourse-cdn.com/julialang/original/3X/0/0/000e3c9aa82fa22488165091835872b4c228f713.png)

---

<div class="post-metadata">

**Author:** ![fredrikekre](https://sea2.discourse-cdn.com/julialang/user_avatar/discourse.julialang.org/fredrikekre/32/1688_2.png) [@fredrikekre](https://discourse.julialang.org/u/fredrikekre)\
**Post date:** [February 6, 2022, 2:47pm UTC](https://discourse.julialang.org/t/what-is-the-compat-admonition-in-documenter-used-for/75900/2 "2022-02-06T14:47:48Z")

</div>

Compatibility annotations, for example the note here: [docs.julialang.org/en/v1/base/strings/#Base.isvalid](https://docs.julialang.org/en/v1/base/strings/#Base.isvalid-Tuple%7BAny,%20Any%7D).

---

<div class="post-metadata">

**Author:** ![sylvaticus](https://sea2.discourse-cdn.com/julialang/user_avatar/discourse.julialang.org/sylvaticus/32/203883_2.png) [@sylvaticus](https://discourse.julialang.org/u/sylvaticus)\
**Post date:** [February 6, 2022, 2:49pm UTC](https://discourse.julialang.org/t/what-is-the-compat-admonition-in-documenter-used-for/75900/3 "2022-02-06T14:49:46Z")

</div>

got it! thanks