Unable to chain null coalescing operator (??)

[eladb]

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I tried this:

This doesn't work (@Chriscbr brought this up):

let f = (x: str?, y: str?) => {
  let z = x ?? y ?? "hello";
//        ^^^^^^ Expected optional type, found "str"
  print("x is ${z}");
};

This works:

let f = (x: str?, y: str?) => {
  let z = x ?? (y ?? "hello");
  print("x is ${z}");
};

This is also going to be defined in the spec (#436).

I expected this:

To behave the same as JS's Nullish_coalescing operator.

Instead, this happened:

See above.

Component:

Compiler

Wing Version:

No response

Node.js Version:

No response

Platform(s):

No response

Anything else?

No response

[github-actions]

Hi,

This issue hasn't seen activity in 60 days. Therefore, we are marking this issue as stale for now. It will be closed after 7 days.
Feel free to re-open this issue when there's an update or relevant information to be added.
Thanks!

[eladb]

Here's another use case for this:

if let x = a ?? b { ... }

Both a and b are T? but we get this error:

error: Expected type to be optional, but got "T" instead

[monadabot]

Congrats! 🚀 This was released in Wing 0.61.17.