Variant constructor name collision

1

Can I have two constructor from different variant types with a same name but different parameters?
For example:

type a = 
| A

type b = 
| A(int)

Currently the compiler would complain, and I tried using a.A and b.A to differentiate, but seems it’s not a valid syntax.

2

You need to add the type information for the variable

let x:a = A
let y = A(1)

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3

Oh I see! Actually I’m using it in a pattern matching expression inside a function.

type a = 
| A

type b = 
| A(int)

let f = (item) => switch item {
| A => true
}

So the real problem here is that the compiler cannot infer the correct type of the parameter from the name of the constructor in the first pattern matching clause.
Thanks!

4

You can also put the two types in separate modules:

module A = {
  type t = A
}

module B = {
  type t = A(int)
}

Then you can prefix the variant constructor with its module name to tell the compiler which one you’re referring to:

let f = item =>
  switch item {
  | A.A => true
  }
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