Check if fun is a @nogc function.
static int foo(int x) @nogc pure nothrow; static int goo(int x) pure nothrow; static assert(isNogc!foo); static assert(!isNogc!goo);
http://forum.dlang.org/thread/dyumjfmxmstpgyxbozry@forum.dlang.org
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Check if fun is a @nogc function.