https://issues.dlang.org/show_bug.cgi?id=22447

          Issue ID: 22447
           Summary: std.sumtype.match has poor compile-time performance
           Product: D
           Version: D2
          Hardware: All
                OS: All
            Status: NEW
          Severity: normal
          Priority: P1
         Component: phobos
          Assignee: nobody@puremagic.com
          Reporter: snarwin+bugzilla@gmail.com

See this thread on the D forum:

https://forum.dlang.org/post/bkgvdewkjwthmlfemnjm@forum.dlang.org

Profiling the test suite with LDC's --ftime-trace flag should be the first step here. Additional test cases, especially those derived from real-world code, would be very helpful for this.

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