Remove the concept of crate directive expressions. Issue #604

Author: brson

src/comp/front/ast.rs

@@ -88,8 +88,6 @@ type crate_ = rec(vec[@crate_directive] directives,
                   crate_cfg config);
 
 tag crate_directive_ {
-    cdir_expr(@expr);
-
     // FIXME: cdir_let should be eliminated
     // and redirected to the use of const stmt_decls inside
     // crate directive blocks.

src/comp/front/eval.rs

@@ -196,63 +196,6 @@ fn eval_crate_directive_block(ctx cx, &ast::block blk, str prefix,
     }
 }
 
-fn eval_crate_directive_expr(ctx cx, @ast::expr x, str prefix,
-                             &mutable vec[@ast::view_item] view_items,
-                             &mutable vec[@ast::item] items) {
-    alt (x.node) {
-        case (ast::expr_if(?cond, ?thn, ?elopt)) {
-            auto cv = eval_expr(cx, cond);
-            if (!val_is_bool(cv)) {
-                cx.sess.span_fatal(x.span, "bad cond type in 'if'");
-            }
-            if (val_as_bool(cv)) {
-                ret eval_crate_directive_block(cx, thn, prefix, view_items,
-                                               items);
-            }
-            alt (elopt) {
-                case (some(?els)) {
-                    ret eval_crate_directive_expr(cx, els, prefix,
-                                                  view_items, items);
-                }
-                case (_) {
-                    // Absent-else is ok.
-
-                }
-            }
-        }
-        case (ast::expr_alt(?v, ?arms)) {
-            auto vv = eval_expr(cx, v);
-            for (ast::arm arm in arms) {
-                alt (arm.pat.node) {
-                    case (ast::pat_lit(?lit, _)) {
-                        auto pv = eval_lit(cx, arm.pat.span, lit);
-                        if (val_eq(cx.sess, arm.pat.span, vv, pv)) {
-                            ret eval_crate_directive_block(cx, arm.block,
-                                                           prefix, view_items,
-                                                           items);
-                        }
-                    }
-                    case (ast::pat_wild(_)) {
-                        ret eval_crate_directive_block(cx, arm.block,
-                                                       prefix, view_items,
-                                                       items);
-                    }
-                    case (_) {
-                        cx.sess.span_fatal(arm.pat.span,
-                                         "bad pattern type in 'alt'");
-                    }
-                }
-            }
-            cx.sess.span_fatal(x.span, "no cases matched in 'alt'");
-        }
-        case (ast::expr_block(?block)) {
-            ret eval_crate_directive_block(cx, block, prefix, view_items,
-                                           items);
-        }
-        case (_) { cx.sess.span_fatal(x.span, "unsupported expr type"); }
-    }
-}
-
 fn eval_crate_directive(ctx cx, @ast::crate_directive cdir, str prefix,
                         &mutable vec[@ast::view_item] view_items,
                         &mutable vec[@ast::item] items) {
@@ -261,9 +204,6 @@ fn eval_crate_directive(ctx cx, @ast::crate_directive cdir, str prefix,
             auto v = eval_expr(cx, x);
             eval_crate_directives(cx, cdirs, prefix, view_items, items);
         }
-        case (ast::cdir_expr(?x)) {
-            eval_crate_directive_expr(cx, x, prefix, view_items, items);
-        }
         case (ast::cdir_src_mod(?id, ?file_opt, ?attrs)) {
             auto file_path = id + ".rs";
             alt (file_opt) {

src/comp/front/fold.rs

@@ -139,7 +139,6 @@ fn noop_fold_crate(&crate_ c, ast_fold fld) -> crate_ {
 fn noop_fold_crate_directive(&crate_directive_ cd, ast_fold fld) 
     -> crate_directive_ {
     ret alt(cd) {
-        case(cdir_expr(?e)) { cdir_expr(fld.fold_expr(e)) }
         case(cdir_let(?id, ?e, ?cds)) {
             cdir_let(fld.fold_ident(id), fld.fold_expr(e),
                      map(fld.fold_crate_directive, cds))

src/comp/front/parser.rs

@@ -2412,10 +2412,8 @@ fn parse_crate_directive(&parser p, vec[ast::attribute] first_outer_attr)
         auto vi = parse_view_item(p);
         ret spanned(lo, vi.span.hi, ast::cdir_view_item(vi));
     } else {
-        auto x = parse_expr(p);
-        ret spanned(lo, x.span.hi, ast::cdir_expr(x));
+        ret p.fatal("expected crate directive");
     }
-    fail;
 }
 
 fn parse_crate_directives(&parser p, token::token term,