Use of forall as a sigil
andrey.mokhov at newcastle.ac.uk
Sun Nov 22 11:23:05 UTC 2020
> In the end, I've never loved the forall ... -> syntax, but I've never seen
> anything better.
What about the forall @a. syntax?
sizeOf :: forall @a. Sized a => Int
We already use @ to explicitly specify types, so it seems natural mark type parameters that must be explicitly specified with @ too.
Here's how one would read it: "for all explicitly specified a, ..."
Apologies if this has been discussed and I missed it. It doesn't seem to be mentioned in the Alternatives section of the proposal but perhaps it will just never work for some reason.
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