https://issues.dlang.org/show_bug.cgi?id=23951

          Issue ID: 23951
           Summary: "alias this" not properly dereferenced when the object
                    being looked up is a field of a type
           Product: D
           Version: D2
          Hardware: All
               URL: http://dlang.org/
                OS: All
            Status: NEW
          Severity: major
          Priority: P3
         Component: dmd
          Assignee: nobody@puremagic.com
          Reporter: eyal@weka.io

struct S { int x; }
struct T { S a; alias a this; }
struct U { T t; }
static assert(__traits(hasMember, T, "x"));
static assert(__traits(hasMember, T.init, "x"));
static assert(__traits(hasMember, U.init.t, "x"));
static assert(__traits(hasMember, U.t, "a"));
static assert(__traits(hasMember, U.t, "x")); // only assertion that fails!


if U.t has a type (T), then it should also have access to "x", in the same way.

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