https://issues.dlang.org/show_bug.cgi?id=21663

          Issue ID: 21663
           Summary: std.concurrency.receiveOnly doesn't work with tuples
           Product: D
           Version: D2
          Hardware: x86
                OS: All
            Status: NEW
          Severity: regression
          Priority: P1
         Component: phobos
          Assignee: nobody@puremagic.com
          Reporter: deadalnix@gmail.com

See sample code:

int main() {
  import std.concurrency;
  receiveOnly!(string, bool, bool);
  return 0;
}

This works in 2.094 (and the application from which it is extracted also works) but fails with the following error in 2.095:

/usr/include/dmd/phobos/std/concurrency.d(806): Error: template instance
isAssignable!(string, bool, bool) does not match template declaration
isAssignable(Lhs, Rhs = Lhs)
test.d(3): Error: template instance std.concurrency.receiveOnly!(string, bool,
bool) error instantiating

I have no idea what this error really mean if I'm honest.

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