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Re:Why Haskell? by magicalhippo on Thursday September 12, 2024 @08:34AM (#41520122)
> letting the compiler decide that `Int` is as good as `Maybe Int`

I was thinking more like explicitly telling the compiler that an implicit cast is OK, in other languages done by implementing the implicit cast operator for example.

edit: but if I understood you correctly, Haskell just doesn't support any implicit casting?

Re:Why Haskell? by mrkeen on Thursday September 12, 2024 @08:49AM (#41520274)
It will do some wrangling of literals for you, as long as it can unambiguously decide on an exact type during type-checking.

If no other info is given, it will treat `3 + 3` as Integer + Integer (and emit a compiler warning because it guessed the type).

With `(3 :: Int64) + 3`, the right 3 will resolve to Int64. Same if you swap their positions.

`(3 :: Int64) + (3 :: Int32)` is a compile error.

"Text literals" can become a String, a Text, or a ByteString if you're not explicit about it.

> implicit cast operator

Wouldn't that make it explicit?

Re:Why Haskell? by magicalhippo on Thursday September 12, 2024 @09:23AM (#41520649)
> Wouldn't that make it explicit?

No, the casting is still done implicitly. That is I can make the following compile fine in Delphi if I add an implicit cast operator to either Foo or Bar:

    Foo x := Foo.Create();
    Bar y := x;
If neither of them have a suitable implicit cast operator defined, it will of course fail to compile.

Just an example, nothing unique about Delphi. You can see an example of the operator definition here[1].

[1]: https://docwiki.embarcadero.com/RADStudio/Alexandria/en/Oper...

Re:Why Haskell? by itishappy on Thursday September 12, 2024 @08:54PM (#41527158)
> "Text literals" can become a String, a Text, or a ByteString if you're not explicit about it.

Not without explicitly enabling `OverloadedStrings`!

https://ghc.gitlab.haskell.org/ghc/doc/users_guide/exts/over...