March 10, 2021
https://issues.dlang.org/show_bug.cgi?id=21695

          Issue ID: 21695
           Summary: Add three-way comparison function to std.functional
           Product: D
           Version: D2
          Hardware: All
                OS: All
            Status: NEW
          Severity: enhancement
          Priority: P1
         Component: phobos
          Assignee: nobody@puremagic.com
          Reporter: snarwin+bugzilla@gmail.com

std.functional already contains the two-way comparison functions lessThan, greaterThan, and equalTo. Since D supports three-way comparison natively via opCmp, it should have a three-way comparison function too.

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