Remove be keyword.

Closes rust-lang#2227.

Author: lkuper

doc/rust.md

@@ -210,7 +210,7 @@ The keywords in [source files](#source-files) are the following strings:
 
 ~~~~~~~~ {.keyword}
 alt assert
-be break
+break
 check claim class const cont copy crust
 do
 else enum export

src/librustsyntax/ast.rs

@@ -336,7 +336,6 @@ enum expr_ {
     expr_break,
     expr_cont,
     expr_ret(option<@expr>),
-    expr_be(@expr),
     expr_log(int, @expr, @expr),
 
     expr_new(/* arena */ @expr,

src/librustsyntax/fold.rs

@@ -488,7 +488,6 @@ fn noop_fold_expr(e: expr_, fld: ast_fold) -> expr_ {
           expr_fail(e) { expr_fail(option::map(e, fld.fold_expr)) }
           expr_break | expr_cont { e }
           expr_ret(e) { expr_ret(option::map(e, fld.fold_expr)) }
-          expr_be(e) { expr_be(fld.fold_expr(e)) }
           expr_log(i, lv, e) { expr_log(i, fld.fold_expr(lv),
                                         fld.fold_expr(e)) }
           expr_assert(e) { expr_assert(fld.fold_expr(e)) }

src/librustsyntax/parse/classify.rs

@@ -42,7 +42,6 @@ fn need_parens(expr: @ast::expr, outer_prec: uint) -> bool {
       ast::expr_swap(_, _) { true }
       ast::expr_assign_op(_, _, _) { true }
       ast::expr_ret(_) { true }
-      ast::expr_be(_) { true }
       ast::expr_assert(_) { true }
       ast::expr_check(_, _) { true }
       ast::expr_log(_, _, _) { true }
@@ -55,7 +54,7 @@ fn ends_in_lit_int(ex: @ast::expr) -> bool {
       ast::expr_lit(@{node: ast::lit_int(_, ast::ty_i), _}) { true }
       ast::expr_binary(_, _, sub) | ast::expr_unary(_, sub) |
       ast::expr_move(_, sub) | ast::expr_copy(sub) |
-      ast::expr_assign(_, sub) | ast::expr_be(sub) |
+      ast::expr_assign(_, sub) |
       ast::expr_assign_op(_, _, sub) | ast::expr_swap(_, sub) |
       ast::expr_log(_, _, sub) | ast::expr_assert(sub) |
       ast::expr_check(_, sub) { ends_in_lit_int(sub) }

src/librustsyntax/parse/lexer.rs

@@ -104,7 +104,7 @@ fn is_bin_digit(c: char) -> bool { ret c == '0' || c == '1'; }
 
 fn consume_whitespace_and_comments(rdr: reader) {
     while is_whitespace(rdr.curr) { rdr.bump(); }
-    be consume_any_line_comment(rdr);
+    ret consume_any_line_comment(rdr);
 }
 
 fn consume_any_line_comment(rdr: reader) {
@@ -114,9 +114,9 @@ fn consume_any_line_comment(rdr: reader) {
             while rdr.curr != '\n' && !rdr.is_eof() { rdr.bump(); }
             // Restart whitespace munch.
 
-            be consume_whitespace_and_comments(rdr);
+            ret consume_whitespace_and_comments(rdr);
           }
-          '*' { rdr.bump(); rdr.bump(); be consume_block_comment(rdr); }
+          '*' { rdr.bump(); rdr.bump(); ret consume_block_comment(rdr); }
           _ { ret; }
         }
     }
@@ -140,7 +140,7 @@ fn consume_block_comment(rdr: reader) {
     }
     // restart whitespace munch.
 
-    be consume_whitespace_and_comments(rdr);
+    ret consume_whitespace_and_comments(rdr);
 }
 
 fn scan_exponent(rdr: reader) -> option<str> {

src/librustsyntax/parse/parser.rs

@@ -825,10 +825,6 @@ fn parse_bottom_expr(p: parser) -> pexpr {
     } else if eat_keyword(p, "cont") {
         ex = expr_cont;
         hi = p.span.hi;
-    } else if eat_keyword(p, "be") {
-        let e = parse_expr(p);
-        hi = e.span.hi;
-        ex = expr_be(e);
     } else if eat_keyword(p, "copy") {
         let e = parse_expr(p);
         ex = expr_copy(e);

src/librustsyntax/print/pprust.rs

@@ -80,24 +80,24 @@ fn print_crate_(s: ps, &&crate: @ast::crate) {
     eof(s.s);
 }
 
-fn ty_to_str(ty: @ast::ty) -> str { be to_str(ty, print_type); }
+fn ty_to_str(ty: @ast::ty) -> str { ret to_str(ty, print_type); }
 
-fn pat_to_str(pat: @ast::pat) -> str { be to_str(pat, print_pat); }
+fn pat_to_str(pat: @ast::pat) -> str { ret to_str(pat, print_pat); }
 
-fn expr_to_str(e: @ast::expr) -> str { be to_str(e, print_expr); }
+fn expr_to_str(e: @ast::expr) -> str { ret to_str(e, print_expr); }
 
-fn stmt_to_str(s: ast::stmt) -> str { be to_str(s, print_stmt); }
+fn stmt_to_str(s: ast::stmt) -> str { ret to_str(s, print_stmt); }
 
-fn item_to_str(i: @ast::item) -> str { be to_str(i, print_item); }
+fn item_to_str(i: @ast::item) -> str { ret to_str(i, print_item); }
 
-fn attr_to_str(i: ast::attribute) -> str { be to_str(i, print_attribute); }
+fn attr_to_str(i: ast::attribute) -> str { ret to_str(i, print_attribute); }
 
 fn typarams_to_str(tps: [ast::ty_param]) -> str {
-    be to_str(tps, print_type_params)
+    ret to_str(tps, print_type_params)
 }
 
 fn path_to_str(&&p: @ast::path) -> str {
-    be to_str(p, bind print_path(_, _, false));
+    ret to_str(p, bind print_path(_, _, false));
 }
 
 fn fun_to_str(decl: ast::fn_decl, name: ast::ident,
@@ -174,11 +174,11 @@ fn meta_item_to_str(mi: ast::meta_item) -> str {
 }
 
 fn attribute_to_str(attr: ast::attribute) -> str {
-    be to_str(attr, print_attribute);
+    ret to_str(attr, print_attribute);
 }
 
 fn variant_to_str(var: ast::variant) -> str {
-    be to_str(var, print_variant);
+    ret to_str(var, print_variant);
 }
 
 #[test]
@@ -1102,7 +1102,6 @@ fn print_expr(s: ps, &&expr: @ast::expr) {
           _ { }
         }
       }
-      ast::expr_be(result) { word_nbsp(s, "be"); print_expr(s, result); }
       ast::expr_log(lvl, lexp, expr) {
         alt check lvl {
           1 { word_nbsp(s, "log"); print_expr(s, expr); }
@@ -1149,7 +1148,7 @@ fn print_expr_parens_if_not_bot(s: ps, ex: @ast::expr) {
       ast::expr_fail(_) | ast::expr_ret(_) |
       ast::expr_binary(_, _, _) | ast::expr_unary(_, _) |
       ast::expr_move(_, _) | ast::expr_copy(_) |
-      ast::expr_assign(_, _) | ast::expr_be(_) |
+      ast::expr_assign(_, _) |
       ast::expr_assign_op(_, _, _) | ast::expr_swap(_, _) |
       ast::expr_log(_, _, _) | ast::expr_assert(_) |
       ast::expr_call(_, _, true) |
@@ -1623,7 +1622,7 @@ fn print_literal(s: ps, &&lit: @ast::lit) {
     }
 }
 
-fn lit_to_str(l: @ast::lit) -> str { be to_str(l, print_literal); }
+fn lit_to_str(l: @ast::lit) -> str { ret to_str(l, print_literal); }
 
 fn next_lit(s: ps, pos: uint) -> option<comments::lit> {
     alt s.literals {

src/librustsyntax/visit.rs

@@ -422,7 +422,6 @@ fn visit_expr<E>(ex: @expr, e: E, v: vt<E>) {
       expr_break { }
       expr_cont { }
       expr_ret(eo) { visit_expr_opt(eo, e, v); }
-      expr_be(x) { v.visit_expr(x, e, v); }
       expr_log(_, lv, x) {
         v.visit_expr(lv, e, v);
         v.visit_expr(x, e, v);

src/libstd/ufind.rs

@@ -28,7 +28,7 @@ fn grow(ufnd: ufind, n: uint) {
 fn find(ufnd: ufind, n: uint) -> uint {
     alt ufnd.nodes[n] {
       none { ret n; }
-      some(m) { let m_ = m; be find(ufnd, m_); }
+      some(m) { let m_ = m; ret find(ufnd, m_); }
     }
 }
 

src/rustc/middle/borrowck.rs

@@ -972,7 +972,7 @@ impl categorize_methods for borrowck_ctxt {
           ast::expr_swap(*) | ast::expr_move(*) | ast::expr_assign(*) |
           ast::expr_assign_op(*) | ast::expr_fn(*) | ast::expr_fn_block(*) |
           ast::expr_assert(*) | ast::expr_check(*) | ast::expr_ret(*) |
-          ast::expr_be(*) | ast::expr_loop_body(*) | ast::expr_unary(*) |
+          ast::expr_loop_body(*) | ast::expr_unary(*) |
           ast::expr_copy(*) | ast::expr_cast(*) | ast::expr_fail(*) |
           ast::expr_vstore(*) | ast::expr_vec(*) | ast::expr_tup(*) |
           ast::expr_if_check(*) | ast::expr_if(*) | ast::expr_log(*) |

src/rustc/middle/check_loop.rs

@@ -44,12 +44,6 @@ fn check_crate(tcx: ty::ctxt, crate: @crate) {
                 }
                 visit::visit_expr_opt(oe, cx, v);
               }
-              expr_be(re) {
-                if !cx.can_ret {
-                    tcx.sess.span_err(e.span, "`be` in block function");
-                }
-                v.visit_expr(re, cx, v);
-              }
               _ { visit::visit_expr(e, cx, v); }
             }
         }

src/rustc/middle/trans/base.rs

@@ -3267,9 +3267,6 @@ fn trans_expr(bcx: block, e: @ast::expr, dest: dest) -> block {
         assert dest == ignore;
         ret trans_ret(bcx, ex);
       }
-      ast::expr_be(ex) {
-        ret trans_be(bcx, ex);
-      }
       ast::expr_fail(expr) {
         assert dest == ignore;
         ret trans_fail_expr(bcx, some(e.span), expr);
@@ -3641,13 +3638,6 @@ fn build_return(bcx: block) {
     Br(bcx, bcx.fcx.llreturn);
 }
 
-fn trans_be(cx: block, e: @ast::expr) -> block {
-    // FIXME: Turn this into a real tail call once
-    // calling convention issues are settled
-    let _icx = cx.insn_ctxt("trans_be");
-    ret trans_ret(cx, some(e));
-}
-
 fn init_local(bcx: block, local: @ast::local) -> block {
     let _icx = bcx.insn_ctxt("init_local");
     let ty = node_id_type(bcx, local.node.id);

src/rustc/middle/trans/type_use.rs

@@ -172,7 +172,7 @@ fn mark_for_expr(cx: ctx, e: @expr) {
         }
       }
       expr_assign(val, _) | expr_swap(val, _) | expr_assign_op(_, val, _) |
-      expr_ret(some(val)) | expr_be(val) {
+      expr_ret(some(val)) {
         node_type_needs(cx, use_repr, val.id);
       }
       expr_index(base, _) | expr_field(base, _, _) {

src/rustc/middle/tstate/ann.rs

@@ -41,13 +41,15 @@ type pre_and_post_state = {prestate: prestate, poststate: poststate};
 
 type ts_ann = @{conditions: pre_and_post, states: pre_and_post_state};
 
-fn true_precond(num_vars: uint) -> precond { be create_tritv(num_vars); }
+fn true_precond(num_vars: uint) -> precond { ret create_tritv(num_vars); }
 
-fn true_postcond(num_vars: uint) -> postcond { be true_precond(num_vars); }
+fn true_postcond(num_vars: uint) -> postcond { ret true_precond(num_vars); }
 
-fn empty_prestate(num_vars: uint) -> prestate { be true_precond(num_vars); }
+fn empty_prestate(num_vars: uint) -> prestate { ret true_precond(num_vars); }
 
-fn empty_poststate(num_vars: uint) -> poststate { be true_precond(num_vars); }
+fn empty_poststate(num_vars: uint) -> poststate {
+    ret true_precond(num_vars);
+}
 
 fn false_postcond(num_vars: uint) -> postcond {
     let rslt = create_tritv(num_vars);

src/rustc/middle/tstate/pre_post_conditions.rs

@@ -391,11 +391,6 @@ fn find_pre_post_expr(fcx: fn_ctxt, e: @expr) {
           }
         }
       }
-      expr_be(val) {
-        find_pre_post_expr(fcx, val);
-        set_pre_and_post(fcx.ccx, e.id, expr_prestate(fcx.ccx, val),
-                         false_postcond(num_local_vars));
-      }
       expr_if(antec, conseq, maybe_alt) {
         join_then_else(fcx, antec, conseq, maybe_alt, e.id, plain_if);
       }

src/rustc/middle/tstate/states.rs

@@ -483,14 +483,6 @@ fn find_pre_post_state_expr(fcx: fn_ctxt, pres: prestate, e: @expr) -> bool {
         }
         ret changed;
       }
-      expr_be(val) {
-        let mut changed = set_prestate_ann(fcx.ccx, e.id, pres);
-        let post = false_postcond(num_constrs);
-        // except for the "diverges" bit...
-        kill_poststate_(fcx, fcx.enclosing.i_diverge, post);
-        set_poststate_ann(fcx.ccx, e.id, post);
-        ret changed | find_pre_post_state_expr(fcx, pres, val);
-      }
       expr_if(antec, conseq, maybe_alt) {
         ret join_then_else(fcx, antec, conseq, maybe_alt, e.id, plain_if,
                            pres);

src/rustc/middle/ty.rs

@@ -1456,7 +1456,7 @@ fn is_instantiable(cx: ctxt, r_ty: t) -> bool {
           ty_box(mt) |
           ty_uniq(mt) |
           ty_rptr(_, mt) {
-            be type_requires(cx, seen, r_ty, mt.ty);
+            ret type_requires(cx, seen, r_ty, mt.ty);
           }
 
           ty_ptr(mt) {

src/rustc/middle/typeck.rs

@@ -3364,15 +3364,6 @@ fn check_expr_with_unifier(fcx: @fn_ctxt,
         }
         fcx.write_bot(id);
       }
-      ast::expr_be(e) {
-        if !ast_util::is_call_expr(e) {
-           tcx.sess.span_err(expr.span,
-              "non-call expression in tail call");
-        }
-        check_expr_with(fcx, e, fcx.ret_ty);
-        bot = true;
-        fcx.write_nil(id);
-      }
       ast::expr_log(_, lv, e) {
         bot = check_expr_with(fcx, lv, ty::mk_mach_uint(tcx, ast::ty_u32));
         // Note: this does not always execute, so do not propagate bot:

src/test/bench/99bob-tail.rs

@@ -12,21 +12,21 @@ fn main() {
         #debug("Take one down and pass it around, %d \
                 bottles of beer on the wall.", n-1);
         #debug("");
-        if n > 3 { be multiple(n - 1); } else { be dual(); }
+        if n > 3 { ret multiple(n - 1); } else { ret dual(); }
     }
     fn dual() {
         #debug("2 bottles of beer on the wall, 2 bottles of beer,");
         #debug("Take one down and pass it around, \
                 1 bottle of beer on the wall.");
         #debug("");
-        be single();
+        ret single();
     }
     fn single() {
         #debug("1 bottle of beer on the wall, 1 bottle of beer,");
         #debug("Take one down and pass it around, \
                 no more bottles of beer on the wall.");
         #debug("");
-        be none();
+        ret none();
     }
     fn none() {
         #debug("No more bottles of beer on the wall, \

src/test/bench/shootout-fasta.rs

@@ -35,8 +35,8 @@ fn select_random(r: u32, genelist: [aminoacids]) -> char {
         if hi > lo + 1u {
             let mid: uint = lo + (hi - lo) / 2u;
             if target < v[mid].prob {
-                be bisect(v, lo, mid, target);
-            } else { be bisect(v, mid, hi, target); }
+                ret bisect(v, lo, mid, target);
+            } else { ret bisect(v, mid, hi, target); }
         } else { ret v[hi].ch; }
     }
     ret bisect(genelist, 0u, vec::len::<aminoacids>(genelist) - 1u, r);

src/test/compile-fail/dead-code-be.rs

@@ -1,7 +1,7 @@
 // -*- rust -*-
 // error-pattern: not all control paths return a value
 
-fn god_exists(a: int) -> bool { be god_exists(a); }
+fn god_exists(a: int) -> bool { ret god_exists(a); }
 
 fn f(a: int) -> int { if god_exists(a) { ret 5; }; }
 

src/test/compile-fail/forgot-ret.rs

@@ -1,6 +1,6 @@
 // error-pattern: mismatched types
 
-fn f() -> int { be g(); }
+fn f() -> int { ret g(); }
 
 fn g() -> uint { ret 0u; }
 

src/test/compile-fail/tail-non-call.rs

@@ -2,6 +2,6 @@
 
 
 // use of tail calls causes arg slot leaks, issue #160.
-fn inner(dummy: str, b: bool) { if b { be inner(dummy, false); } }
+fn inner(dummy: str, b: bool) { if b { ret inner(dummy, false); } }
 
 fn main() { inner("hi", true); }

src/test/compile-fail/tail-typeck.rs

@@ -9,11 +9,11 @@ fn main() { let k = checktrue; evenk(42, k); oddk(45, k); }
 fn evenk(n: int, k: native fn(bool) -> bool) -> bool {
     #debug("evenk");
     log(debug, n);
-    if n == 0 { be k(true); } else { be oddk(n - 1, k); }
+    if n == 0 { ret k(true); } else { ret oddk(n - 1, k); }
 }
 
 fn oddk(n: int, k: native fn(bool) -> bool) -> bool {
     #debug("oddk");
     log(debug, n);
-    if n == 0 { be k(false); } else { be evenk(n - 1, k); }
+    if n == 0 { ret k(false); } else { ret evenk(n - 1, k); }
 }