Add identity functor to base
base already provides a Constant functor, but the even more useful Identity (or Identity) functor does not exist in base yet.
This was already proposed to the CLC back in early 2013, and already missed inclusion in GHC 7.8
However, in order to implement this, coordination with transformers is desirable, as transformers currently provides a non-transforming Data.Functor.Identity, and we'd like to avoid name clashes.
Trac metadata
| Trac field | Value |
|---|---|
| Version | |
| Type | Task |
| TypeOfFailure | OtherFailure |
| Priority | normal |
| Resolution | Unresolved |
| Component | Core Libraries |
| Test case | |
| Differential revisions | |
| BlockedBy | |
| Related | |
| Blocking | |
| CC | ekmett, ross, simonpj |
| Operating system | |
| Architecture |