https://issues.dlang.org/show_bug.cgi?id=21338

          Issue ID: 21338
           Summary: Move functional style code's unit tests outside scope,
                    to actually test them.
           Product: D
           Version: D2
          Hardware: x86_64
                OS: Linux
            Status: NEW
          Severity: enhancement
          Priority: P1
         Component: phobos
          Assignee: nobody@puremagic.com
          Reporter: crazymonkyyy@gmail.com

https://run.dlang.io/is/UxBhfw

import std;
void main()
{
  writeln("Learning D is fun".split!isWhite);
}

This is copy and pasted from the unittests, it behaves different based on scope
to the point I'm not sure "auto split(alias isTerminator, Range)(Range range)"
can exist outside of std code.

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