https://issues.dlang.org/show_bug.cgi?id=13643

          Issue ID: 13643
           Summary: memoize lazy parameter evaluation
           Product: D
           Version: unspecified
          Hardware: All
                OS: All
            Status: NEW
          Severity: enhancement
          Priority: P1
         Component: DMD
          Assignee: nobody@puremagic.com
          Reporter: code@dawg.eu

Currently D's lazy parameters use call-by-name, i.e. the expression is evaluated whenever referenced. Historically lazy refers to call-by-need evaluation where the result is cached on first use. http://en.wikipedia.org/wiki/Evaluation_strategy#Call_by_name

We could at least do it for pure expressions that are referenced multiple times.

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