Remove match check

Author: catamorphism

src/libsyntax/ast.rs

@@ -348,7 +348,7 @@ enum expr_ {
        Same semantics as while(true) { body }, but typestate knows that the
        (implicit) condition is always true. */
     expr_loop(blk, option<ident>),
-    expr_match(@expr, ~[arm], alt_mode),
+    expr_match(@expr, ~[arm]),
     expr_fn(proto, fn_decl, blk, capture_clause),
     expr_fn_block(fn_decl, blk, capture_clause),
     // Inner expr is always an expr_fn_block. We need the wrapping node to

src/libsyntax/ext/auto_serialize.rs

@@ -250,7 +250,7 @@ impl ext_ctxt: ext_ctxt_helpers {
         self.stmt(
             self.expr(
                 span,
-                ast::expr_match(v, arms, ast::alt_exhaustive)))
+                ast::expr_match(v, arms)))
     }
 
     fn lit_str(span: span, s: @~str) -> @ast::expr {
@@ -944,7 +944,7 @@ fn deser_enum(cx: ext_ctxt, tps: deser_tps_map, e_name: ast::ident,
     // Generate code like:
     let e_name = cx.lit_str(e_span, @cx.str_of(e_name));
     let alt_expr = cx.expr(e_span,
-                   ast::expr_match(#ast{__i}, arms, ast::alt_exhaustive));
+                           ast::expr_match(#ast{__i}, arms));
     let var_lambda = #ast{ |__i| $(alt_expr) };
     let read_var = #ast{ $(cx.clone(d)).read_enum_variant($(var_lambda)) };
     let read_lambda = cx.lambda(cx.expr_blk(read_var));

src/libsyntax/fold.rs

@@ -456,9 +456,9 @@ fn noop_fold_expr(e: expr_, fld: ast_fold) -> expr_ {
               expr_loop(fld.fold_block(body),
                         option::map(opt_ident, |x| fld.fold_ident(x)))
           }
-          expr_match(expr, arms, mode) => {
+          expr_match(expr, arms) => {
             expr_match(fld.fold_expr(expr),
-                     vec::map(arms, |x| fld.fold_arm(x)), mode)
+                     vec::map(arms, |x| fld.fold_arm(x)))
           }
           expr_fn(proto, decl, body, captures) => {
             expr_fn(proto, fold_fn_decl(decl, fld),

src/libsyntax/parse/parser.rs

@@ -1668,8 +1668,6 @@ struct parser {
 
     fn parse_alt_expr() -> @expr {
         let lo = self.last_span.lo;
-        let mode = if self.eat_keyword(~"check") { alt_check }
-        else { alt_exhaustive };
         let discriminant = self.parse_expr();
         self.expect(token::LBRACE);
         let mut arms: ~[arm] = ~[];
@@ -1701,7 +1699,7 @@ struct parser {
         }
         let mut hi = self.span.hi;
         self.bump();
-        return self.mk_expr(lo, hi, expr_match(discriminant, arms, mode));
+        return self.mk_expr(lo, hi, expr_match(discriminant, arms));
     }
 
     fn parse_expr() -> @expr {

src/libsyntax/print/pprust.rs

@@ -1128,11 +1128,10 @@ fn print_expr(s: ps, &&expr: @ast::expr) {
         option::iter(opt_ident, |ident| {print_ident(s, ident); space(s.s)});
         print_block(s, blk);
       }
-      ast::expr_match(expr, arms, mode) => {
+      ast::expr_match(expr, arms) => {
         cbox(s, alt_indent_unit);
         ibox(s, 4u);
         word_nbsp(s, ~"match");
-        if mode == ast::alt_check { word_nbsp(s, ~"check"); }
         print_maybe_parens_discrim(s, expr);
         space(s.s);
         bopen(s);

src/libsyntax/visit.rs

@@ -430,7 +430,7 @@ fn visit_expr<E>(ex: @expr, e: E, v: vt<E>) {
       }
       expr_while(x, b) => { v.visit_expr(x, e, v); v.visit_block(b, e, v); }
       expr_loop(b, _) => v.visit_block(b, e, v),
-      expr_match(x, arms, _) => {
+      expr_match(x, arms) => {
         v.visit_expr(x, e, v);
         for arms.each |a| { v.visit_arm(a, e, v); }
       }

src/rustc/middle/borrowck/gather_loans.rs

@@ -171,7 +171,7 @@ fn req_loans_in_expr(ex: @ast::expr,
         visit::visit_expr(ex, self, vt);
       }
 
-      ast::expr_match(ex_v, arms, _) => {
+      ast::expr_match(ex_v, arms) => {
         let cmt = self.bccx.cat_expr(ex_v);
         for arms.each |arm| {
             for arm.pats.each |pat| {

src/rustc/middle/check_alt.rs

@@ -24,7 +24,7 @@ fn check_crate(tcx: ty::ctxt, crate: @crate) {
 fn check_expr(tcx: ty::ctxt, ex: @expr, &&s: (), v: visit::vt<()>) {
     visit::visit_expr(ex, s, v);
     match ex.node {
-      expr_match(scrut, arms, mode) => {
+      expr_match(scrut, arms) => {
         check_arms(tcx, arms);
         /* Check for exhaustiveness */
          // Check for empty enum, because is_useful only works on inhabited
@@ -48,13 +48,10 @@ fn check_expr(tcx: ty::ctxt, ex: @expr, &&s: (), v: visit::vt<()>) {
           }
           _ => { /* We assume only enum types can be uninhabited */ }
        }
-
-        if mode == alt_exhaustive {
-            let arms = vec::concat(vec::filter_map(arms, unguarded_pat));
-            check_exhaustive(tcx, ex.span, arms);
-        }
-      }
-      _ => ()
+       let arms = vec::concat(vec::filter_map(arms, unguarded_pat));
+       check_exhaustive(tcx, ex.span, arms);
+     }
+     _ => ()
     }
 }
 

src/rustc/middle/liveness.rs

@@ -1048,7 +1048,7 @@ impl Liveness {
             self.propagate_through_loop(expr, none, blk, succ)
           }
 
-          expr_match(e, arms, _) => {
+          expr_match(e, arms) => {
             //
             //      (e)
             //       |

src/rustc/middle/region.rs

@@ -259,7 +259,7 @@ fn resolve_expr(expr: @ast::expr, cx: ctxt, visitor: visit::vt<ctxt>) {
                                                            cx.sess.intr()));
         new_cx.parent = some(expr.id);
       }
-      ast::expr_match(subexpr, _, _) => {
+      ast::expr_match(subexpr, _) => {
         debug!("node %d: %s", expr.id, pprust::expr_to_str(expr,
                                                            cx.sess.intr()));
         new_cx.parent = some(expr.id);

src/rustc/middle/trans/alt.rs

@@ -822,16 +822,15 @@ fn trans_alt(bcx: block,
              alt_expr: @ast::expr,
              expr: @ast::expr,
              arms: ~[ast::arm],
-             mode: ast::alt_mode,
              dest: dest) -> block {
     let _icx = bcx.insn_ctxt("alt::trans_alt");
     do with_scope(bcx, alt_expr.info(), ~"alt") |bcx| {
-        trans_alt_inner(bcx, expr, arms, mode, dest)
+        trans_alt_inner(bcx, expr, arms, dest)
     }
 }
 
 fn trans_alt_inner(scope_cx: block, expr: @ast::expr, arms: ~[ast::arm],
-                   mode: ast::alt_mode, dest: dest) -> block {
+                   dest: dest) -> block {
     let _icx = scope_cx.insn_ctxt("alt::trans_alt_inner");
     let bcx = scope_cx, tcx = bcx.tcx();
     let mut bodies = ~[], matches = ~[];
@@ -860,15 +859,7 @@ fn trans_alt_inner(scope_cx: block, expr: @ast::expr, arms: ~[ast::arm],
             return fail_cx.llbb;
     }
     let t = node_id_type(bcx, expr.id);
-    let mk_fail = match mode {
-      ast::alt_check => {
-        let fail_cx = @mut none;
-        // Cached fail-on-fallthrough block
-        some(|| mk_fail(scope_cx, expr.span, ~"non-exhaustive match failure",
-                        fail_cx))
-      }
-      ast::alt_exhaustive => {
-          let fail_cx = @mut none;
+    let mk_fail = { let fail_cx = @mut none;
           // special case for uninhabited type
           if ty::type_is_empty(tcx, t) {
                   some(|| mk_fail(scope_cx, expr.span,
@@ -877,7 +868,6 @@ fn trans_alt_inner(scope_cx: block, expr: @ast::expr, arms: ~[ast::arm],
           else {
               none
           }
-      }
     };
     let mut exit_map = ~[];
     let spilled = spill_if_immediate(bcx, val, t);

src/rustc/middle/trans/base.rs

@@ -3798,8 +3798,8 @@ fn trans_expr(bcx: block, e: @ast::expr, dest: dest) -> block {
           ast::expr_if(cond, thn, els) => {
             return trans_if(bcx, cond, thn, els, dest);
           }
-          ast::expr_match(expr, arms, mode) => {
-            return alt::trans_alt(bcx, e, expr, arms, mode, dest);
+          ast::expr_match(expr, arms) => {
+            return alt::trans_alt(bcx, e, expr, arms, dest);
           }
           ast::expr_block(blk) => {
             return do with_scope(bcx, blk.info(), ~"block-expr body") |bcx| {
@@ -4488,7 +4488,7 @@ fn trans_block_cleanups_(bcx: block,
                 }
               }
             }
-            }
+        }
     return bcx;
 }
 

src/rustc/middle/typeck/check.rs

@@ -1599,7 +1599,7 @@ fn check_expr_with_unifier(fcx: @fn_ctxt,
         fcx.write_ty(id, ty::mk_nil(tcx));
         bot = !may_break(body);
       }
-      ast::expr_match(discrim, arms, mode) => {
+      ast::expr_match(discrim, arms) => {
         bot = alt::check_alt(fcx, expr, discrim, arms);
       }
       ast::expr_fn(proto, decl, body, cap_clause) => {