problem while updating to 2.052

[Christian Köstlin]

hi .. i have a small library for combinatorial parsing.
when i updated to version 2.052 of dmd (tested on os x) i got an 
exception from variant.d:279 (target must be non-null).
i fixed the problem with the following diff:
      ParseResult!(T) parse(T[] s) {
-      auto results = appender!(Variant[])();
+      Variant[] results;
        auto rest = s;
        while (true) {
          auto res = fToRepeat.parse(rest);
          if (res.success) {
            rest = res.rest;
-          results.put(res.results);
+          results = results ~ res.results;
          } else {
            break;
          }
        }
-      return transform(ParseResult!(T).ok(rest, results.data));
+      return transform(ParseResult!(T).ok(rest, results));
      }

what did i do wrong and why could it work with an older version of dmd2?

thanks in advance

christian koestlin