Page URL

https://dart.dev/language/pattern-types#map

Page source

No response

Describe the problem

Consider the following code:

void main() {
  final {'foo': int? foo} = {};
  print(foo);
}

This causes a StateError to be thrown as you can't match a key that doesn't exist in the map. We should document this behavior as it's not mentioned anywhere

Expected fix

Add a warning about this behavior on https://dart.dev/language/pattern-types#map

Additional context

No response

I would like to fix this problem.

• I will try and fix this problem on dart.dev.