f＃表达式的类型

Question

I'm looking for a way to find out the type of an f# expression. Something similar to Haskell's type function.

Answer 1

IDE:s like VS & VS Code (+ Ionide) can help you with this. Otherwise what I do is that I assign the expression to an obviously invalid binding like:

let x : unit = <the_expression>

The compiler will fail and tell you what it found that didn't match unit. If the compiler doesn't fail the _ expression is unit. I don't think there's some like _ in haskell to ask the compiler "What do you expect here?".