https://issues.dlang.org/show_bug.cgi?id=23635

          Issue ID: 23635
           Summary: Nonsensical "`case` must be a `string` or an integral
                    constant, not `x`"
           Product: D
           Version: D2
          Hardware: All
                OS: All
            Status: NEW
          Severity: minor
          Priority: P4
         Component: dmd
          Assignee: nobody@puremagic.com
          Reporter: dkorpel@live.nl

```
void main()
{
    immutable string x, y;
    switch (y) {
        case x: break;
        default: break;
    }
}
```

> onlineapp.d(6): Error: `case` must be a `string` or an integral constant, not `x`

x is a string in this case, so the error is nonsensical.

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