https://issues.dlang.org/show_bug.cgi?id=21907

          Issue ID: 21907
           Summary: The number of templates instantiated when doing just
                    `import std;` is too damn high
           Product: D
           Version: D2
          Hardware: All
                OS: All
            Status: NEW
          Severity: enhancement
          Priority: P1
         Component: phobos
          Assignee: nobody@puremagic.com
          Reporter: andrei@erdani.com

Ideally there should be virtually no work done when the standard library is imported but not used.

First step:

https://github.com/dlang/phobos/pull/8053

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