https://issues.dlang.org/show_bug.cgi?id=23620

          Issue ID: 23620
           Summary: 'alias this' is not respected in static array length
                    position
           Product: D
           Version: D2
          Hardware: All
                OS: All
            Status: NEW
          Keywords: rejects-valid
          Severity: normal
          Priority: P1
         Component: dmd
          Assignee: nobody@puremagic.com
          Reporter: maxsamukha@gmail.com

struct Index
{
    uint value;
    alias value this;
}

enum i = Index();
int[i] a;

void main()
{
}

Error: integer constant expression expected instead of `Index(0u)`

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