# Signature and unit

**URL:** <https://racket.discourse.group/t/signature-and-unit/1295>\
**Category:** Questions & Answers\
**Created:** [September 10, 2022, 7:24am UTC](https://racket.discourse.group/t/signature-and-unit/1295 "2022-09-10T07:24:45Z")\
**Posts on this page:** 1\
**Page:** 1

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**Author:** ![dannypsnl](https://yyz2.discourse-cdn.com/free1/user_avatar/racket.discourse.group/dannypsnl/32/917_2.png) [@dannypsnl](https://racket.discourse.group/u/dannypsnl)\
**Post date:** [September 10, 2022, 7:24am UTC](https://racket.discourse.group/t/signature-and-unit/1295/1 "2022-09-10T07:24:45Z")

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If I define a `signature`, then the `unit` exports it has to implement all identifiers as I know, does there has any abstraction is that I can provide default implementation like replying **unsupported** with a brief interface like `signature`? Or a `unit` can do this actually?