https://issues.dlang.org/show_bug.cgi?id=18669

          Issue ID: 18669
           Summary: isNestedFunction does not check if parameter is a
                    function
           Product: D
           Version: D2
          Hardware: All
                OS: All
            Status: NEW
          Severity: normal
          Priority: P1
         Component: phobos
          Assignee: nobody@puremagic.com
          Reporter: jack@jackstouffer.com

import std.traits;

class Outer
{
    class Inner
    {
    }
}

void main()
{
    void fun(int i);
    int i;
    struct SS
    {
        int bar() { return i; }
    }
    static assert(isNestedFunction!(fun));
    static assert(isNestedFunction!(SS));
    static assert(isNestedFunction!(Outer.Inner));
}

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