Adjust AST encoding, teach fold about linear for loops.

1 files changed, 18 insertions, 0 deletions

diff --git a/src/comp/middle/fold.rs b/src/comp/middle/fold.rs
index 618790ee..d8688e00 100644
--- a/src/comp/middle/fold.rs
+++ b/src/comp/middle/fold.rs
@@ -104,6 +104,10 @@ type ast_fold[ENV] =
          ann a) -> @expr)                         fold_expr_if,
 
      (fn(&ENV e, &span sp,
+         @decl decl, @expr seq, &block body,
+         ann a) -> @expr)                         fold_expr_for,
+
+     (fn(&ENV e, &span sp,
          @expr cond, &block body,
          ann a) -> @expr)                         fold_expr_while,
 
@@ -509,6 +513,13 @@ fn fold_expr[ENV](&ENV env, ast_fold[ENV] fld, &@expr e) -> @expr {
             ret fld.fold_expr_if(env_, e.span, ccnd, tthn, eels, t);
         }
 
+        case (ast.expr_for(?decl, ?seq, ?body, ?t)) {
+            auto ddecl = fold_decl(env_, fld, decl);
+            auto sseq = fold_expr(env_, fld, seq);
+            auto bbody = fold_block(env_, fld, body);
+            ret fld.fold_expr_for(env_, e.span, ddecl, seq, bbody, t);
+        }
+
         case (ast.expr_while(?cnd, ?body, ?t)) {
             auto ccnd = fold_expr(env_, fld, cnd);
             auto bbody = fold_block(env_, fld, body);
@@ -950,6 +961,12 @@ fn identity_fold_expr_if[ENV](&ENV env, &span sp,
     ret @respan(sp, ast.expr_if(cond, thn, els, a));
 }
 
+fn identity_fold_expr_for[ENV](&ENV env, &span sp,
+                               @decl d, @expr seq,
+                               &block body, ann a) -> @expr {
+    ret @respan(sp, ast.expr_for(d, seq, body, a));
+}
+
 fn identity_fold_expr_while[ENV](&ENV env, &span sp,
                                  @expr cond, &block body, ann a) -> @expr {
     ret @respan(sp, ast.expr_while(cond, body, a));
@@ -1214,6 +1231,7 @@ fn new_identity_fold[ENV]() -> ast_fold[ENV] {
          fold_expr_lit    = bind identity_fold_expr_lit[ENV](_,_,_,_),
          fold_expr_cast   = bind identity_fold_expr_cast[ENV](_,_,_,_,_),
          fold_expr_if     = bind identity_fold_expr_if[ENV](_,_,_,_,_,_),
+         fold_expr_for    = bind identity_fold_expr_for[ENV](_,_,_,_,_,_),
          fold_expr_while  = bind identity_fold_expr_while[ENV](_,_,_,_,_),
          fold_expr_do_while
                           = bind identity_fold_expr_do_while[ENV](_,_,_,_,_),