https://issues.dlang.org/show_bug.cgi?id=20332

          Issue ID: 20332
           Summary: associative array clear function should be @safe
           Product: D
           Version: D2
          Hardware: All
                OS: All
            Status: NEW
          Severity: enhancement
          Priority: P1
         Component: druntime
          Assignee: nobody@puremagic.com
          Reporter: schveiguy@yahoo.com

If you look at the implementation of clear, it does not invalidate any items in the array. It just sets to null all the pointers to bucket items. The items themselves remain allocated, and any range that is pointing at a null bucket item will return null for the key or value, causing a null dereference (which is considered @safe).

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