https://issues.dlang.org/show_bug.cgi?id=21264

          Issue ID: 21264
           Summary: Template constraint on `each` is too wide
           Product: D
           Version: D2
          Hardware: x86_64
                OS: Linux
            Status: NEW
          Severity: enhancement
          Priority: P1
         Component: phobos
          Assignee: nobody@puremagic.com
          Reporter: timon.gehr@gmx.ch

----
import std.algorithm;
struct S{
    struct T{
        struct Q{}
        Q length;
    }
    T front;
}

void main(){
    S().each!((x){});
}
----
std/algorithm/iteration.d(966): Error: template `std.range.primitives.empty`
cannot deduce function from argument types `!()(S)`, candidates are:
...
----

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