Optional-named params do not work with function expressions.

[DartBot]

This issue was originally filed by [email protected]

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The following error occurs in the VM and cannot be replicated on http://try.dartlang.org/

The following code emits this error (unexpected token ':'):

void f([num x = 0, num y = 0]) {}
main() => f(x:12, y:13);

This variant works just fine:

void f([num x = 0, num y = 0]) {}
main() {
  f(x:12, y:13);
}

[DartBot]

This comment was originally written by [email protected]

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Added Triaged label.

[iposva-google]

Cannot reproduce any longer.

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Added CannotReproduce label.