https://issues.dlang.org/show_bug.cgi?id=23524

          Issue ID: 23524
           Summary: Allow user-defined value ranges for aggregate fields
           Product: D
           Version: D2
          Hardware: All
                OS: All
            Status: NEW
          Severity: enhancement
          Priority: P1
         Component: dmd
          Assignee: nobody@puremagic.com
          Reporter: john.michael.hall@gmail.com

>From
https://forum.dlang.org/post/ooraoriyrftjrpoygtnk@forum.dlang.org

User-defined value ranges for aggregate fields (e.g., pointer that can't be null, integer that can't go above/below a certain limit).

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