https://issues.dlang.org/show_bug.cgi?id=12599

          Issue ID: 12599
           Summary: templated inout opIndex gives strange error
           Product: D
           Version: unspecified
          Hardware: All
                OS: All
            Status: NEW
          Severity: major
          Priority: P1
         Component: DMD
          Assignee: nobody@puremagic.com
          Reporter: temtaime@gmail.com

struct S(T) {
    T[1] a;

    pure ref T opIndex(size_t i) inout { return a[i]; }
}

void main() {
    S!short s;
}

/d952/f855.d(4): Error: cast(short)this.a[i] is not an lvalue /d952/f855.d(8):
Error: template instance f855.S!short error instantiating

If in prototype T is ommited like this

pure ref opIndex(size_t i) inout { return a[i]; }

It compiles ok.

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