54 lines
1.8 KiB
Rust
54 lines
1.8 KiB
Rust
|
import syntax::ast::*;
|
||
|
|
import syntax::visit;
|
||
|
|
import driver::session::session;
|
||
|
|
|
||
|
|
type ctx = {in_loop: bool, can_ret: bool};
|
||
|
|
|
||
|
|
fn check_crate(sess: session, 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>|
|
||
|
|
alt e.node {
|
||
|
|
expr_for(_, e, b) | expr_while(e, b) | expr_do_while(b, e) {
|
||
|
|
v.visit_expr(e, cx, v);
|
||
|
|
v.visit_block(b, {in_loop: true with cx}, v);
|
||
|
|
}
|
||
|
|
expr_loop(b) {
|
||
|
|
v.visit_block(b, {in_loop: true with cx}, v);
|
||
|
|
}
|
||
|
|
expr_fn(_, _, _, _) {
|
||
|
|
visit::visit_expr(e, {in_loop: false, can_ret: true}, v);
|
||
|
|
}
|
||
|
|
expr_fn_block(fn_decl, blk) {
|
||
|
|
visit::visit_expr(e, {in_loop: false, can_ret: false}, v);
|
||
|
|
}
|
||
|
|
expr_break {
|
||
|
|
if !cx.in_loop {
|
||
|
|
sess.span_err(e.span, "`break` outside of loop");
|
||
|
|
}
|
||
|
|
}
|
||
|
|
expr_cont {
|
||
|
|
if !cx.in_loop {
|
||
|
|
sess.span_err(e.span, "`cont` outside of loop");
|
||
|
|
}
|
||
|
|
}
|
||
|
|
expr_ret(oe) {
|
||
|
|
if !cx.can_ret {
|
||
|
|
sess.span_err(e.span, "`ret` in block function");
|
||
|
|
}
|
||
|
|
visit::visit_expr_opt(oe, cx, v);
|
||
|
|
}
|
||
|
|
expr_be(re) {
|
||
|
|
if !cx.can_ret {
|
||
|
|
sess.span_err(e.span, "`be` in block function");
|
||
|
|
}
|
||
|
|
v.visit_expr(re, cx, v);
|
||
|
|
}
|
||
|
|
_ { visit::visit_expr(e, cx, v); }
|
||
|
|
}
|
||
|
|
}
|
||
|
|
with *visit::default_visitor()
|
||
|
|
}));
|
||
|
|
}
|