rustc: Stop generating the flag_none #fmt flag. Issue #1993

Author: brson

src/libcore/extfmt.rs

@@ -269,12 +269,7 @@ mod rt {
         flag_space_for_sign,
         flag_sign_always,
         flag_alternate,
-
-
-        // FIXME: This is a hack to avoid creating 0-length vec exprs,
-        // which have some difficulty typechecking currently. See
-        // comments in front::extfmt::make_flags
-        // (once #1993 is addressed, this won't be necessary)
+        // FIXME(1993): This is no longer needed. Remove after a snapshot
         flag_none,
     }
     enum count { count_is(int), count_implied, }

src/rustc/syntax/ext/fmt.rs

@@ -68,13 +68,6 @@ fn pieces_to_expr(cx: ext_ctxt, sp: span, pieces: [piece], args: [@ast::expr])
                 }
                 flagexprs += [make_rt_path_expr(cx, sp, fstr)];
             }
-            // FIXME: 0-length vectors can't have their type inferred
-            // through the rec that these flags are a member of, so
-            // this is a hack placeholder flag
-
-            if vec::len::<@ast::expr>(flagexprs) == 0u {
-                flagexprs += [make_rt_path_expr(cx, sp, "flag_none")];
-            }
             ret mk_vec_e(cx, sp, flagexprs);
         }
         fn make_count(cx: ext_ctxt, sp: span, cnt: count) -> @ast::expr {