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// Copyright 2012 The Rust Project Developers. See the COPYRIGHT
// file at the top-level directory of this distribution and at
// http://rust-lang.org/COPYRIGHT.
//
// Licensed under the Apache License, Version 2.0 <LICENSE-APACHE or
// http://www.apache.org/licenses/LICENSE-2.0> or the MIT license
// <LICENSE-MIT or http://opensource.org/licenses/MIT>, at your
// option. This file may not be copied, modified, or distributed
// except according to those terms.
use syntax::ast::*;
use syntax::visit;
type ctx = {in_loop: bool, can_ret: bool};
fn check_crate(tcx: ty::ctxt, crate: @crate) {
visit::visit_crate(*crate,
{in_loop: false, can_ret: true},
visit::mk_vt(@{
visit_item: |i, _cx, v| {
visit::visit_item(i, {in_loop: false, can_ret: true}, v);
},
visit_expr: |e: @expr, cx: ctx, v: visit::vt<ctx>| {
match e.node {
expr_while(e, ref b) => {
(v.visit_expr)(e, cx, v);
(v.visit_block)((*b), {in_loop: true,.. cx}, v);
}
expr_loop(ref b, _) => {
(v.visit_block)((*b), {in_loop: true,.. cx}, v);
}
expr_fn(_, _, _, _) => {
visit::visit_expr(e, {in_loop: false, can_ret: true}, v);
}
expr_fn_block(_, ref b, _) => {
(v.visit_block)((*b), {in_loop: false, can_ret: false}, v);
}
expr_loop_body(@{node: expr_fn_block(_, ref b, _), _}) => {
let proto = ty::ty_fn_proto(ty::expr_ty(tcx, e));
let blk = (proto == ProtoBorrowed);
(v.visit_block)((*b), {in_loop: true, can_ret: blk}, v);
}
expr_break(_) => {
if !cx.in_loop {
tcx.sess.span_err(e.span, ~"`break` outside of loop");
}
}
expr_again(_) => {
if !cx.in_loop {
tcx.sess.span_err(e.span, ~"`again` outside of loop");
}
}
expr_ret(oe) => {
if !cx.can_ret {
tcx.sess.span_err(e.span, ~"`return` in block function");
}
visit::visit_expr_opt(oe, cx, v);
}
_ => visit::visit_expr(e, cx, v)
}
},
.. *visit::default_visitor()
}));
}
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