https://issues.dlang.org/show_bug.cgi?id=24450

          Issue ID: 24450
           Summary: apply VRP to foreach indices when array is of known
                    length
           Product: D
           Version: D2
          Hardware: x86_64
                OS: All
            Status: NEW
          Severity: enhancement
          Priority: P1
         Component: dmd
          Assignee: nobody@puremagic.com
          Reporter: bugzilla@digitalmars.com

This:

    foreach (int i, color; [red, green, blue])
        img.fillCircle(50 + i * 20, 30 + i * 10, 20 + i * 5, color);

should not give an error about implicit conversion of 64 bit size_t to int, because the array's length is known to fit in an int.

https://github.com/dlang/dmd/pull/8941#issuecomment-496306412

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