Undeprecate isNull

There's no good reason to deprecate it:
- For consistency reasons it should continue to exist, such that all
primitive types have a corresponding `builtins.is*` primop.
- There's no implementation cost to continuing to have this function
- It costs users time to try to migrate away from it, e.g.
  https://github.com/NixOS/nixpkgs/pull/219747 and https://github.com/NixOS/nixpkgs/pull/275548
- Using it can give easier-to-read code like `all isNull list`

Co-authored-by: Robert Hensing <roberth@users.noreply.github.com>
This commit is contained in:
Silvan Mosberger 2023-12-20 03:24:38 +01:00 committed by Silvan Mosberger
parent 7cfd6c0efe
commit ea454d8687

View file

@ -438,9 +438,7 @@ static RegisterPrimOp primop_isNull({
.doc = R"(
Return `true` if *e* evaluates to `null`, and `false` otherwise.
> **Warning**
>
> This function is *deprecated*; just write `e == null` instead.
This is equivalent to `e == null`.
)",
.fun = prim_isNull,
});