• d-bugmail puremagic.com (31/31) Jul 31 2019 https://issues.dlang.org/show_bug.cgi?id=20093

d-bugmail puremagic.com writes:

https://issues.dlang.org/show_bug.cgi?id=20093

          Issue ID: 20093
           Summary: Error: cannot form tuple of tuples
           Product: D
           Version: D2
          Hardware: x86_64
                OS: All
            Status: NEW
          Severity: normal
          Priority: P1
         Component: dmd
          Assignee: nobody puremagic.com
          Reporter: destructionator gmail.com

mixin template MakeProperty(Attributes...) {
         (Attributes) void bug() {}
}

struct Attr { }

struct Test {
        mixin MakeProperty!(Attr);
}

void main() {
        pragma(msg, __traits(getAttributes, Test.bug).stringof);
}


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Interestingly, it compiles fine if you do not try to actually getAttributes;
comment out that pragma line in main and it works just fine.

It also works if you pass a value to MakeProperty; only a type like in the
example triggers the problem.

In dmd, the comment says "Assume exps[] is already tuple expanded." so I'm
guessing some semantic() pass wasn't run in the right place for this.

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