May 01, 2016
https://issues.dlang.org/show_bug.cgi?id=15981

          Issue ID: 15981
           Summary: infer function types for auto functions
           Product: D
           Version: D2
          Hardware: x86_64
                OS: Linux
            Status: NEW
          Severity: enhancement
          Priority: P1
         Component: dmd
          Assignee: nobody@puremagic.com
          Reporter: greensunny12@gmail.com

> Why didn't we go with all functions being able to infer const, pure etc rather than just templates?

The problem is essentially untractable when there are loops in the call graph.

That being said, it would make sense to do it for auto functions.

(discussion: http://forum.dlang.org/post/esfmscijqfjcfdawkfpe@forum.dlang.org)

I just put this here, so it doesn't get forgotten ;-)

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