106 lines
1.9 KiB
Rust
106 lines
1.9 KiB
Rust
// Copyright 2015 The Rust Project Developers. See the COPYRIGHT
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// file at the top-level directory of this distribution and at
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// http://rust-lang.org/COPYRIGHT.
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//
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// Licensed under the Apache License, Version 2.0 <LICENSE-APACHE or
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// http://www.apache.org/licenses/LICENSE-2.0> or the MIT license
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// <LICENSE-MIT or http://opensource.org/licenses/MIT>, at your
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// option. This file may not be copied, modified, or distributed
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// except according to those terms.
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// Test various cases where we permit an unconstrained variable
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// to fallback based on control-flow.
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//
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// These represent current behavior, but are pretty dubious. I would
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// like to revisit these and potentially change them. --nmatsakis
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#![feature(never_type)]
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trait BadDefault {
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fn default() -> Self;
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}
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impl BadDefault for u32 {
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fn default() -> Self {
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0
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}
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}
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impl BadDefault for ! {
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fn default() -> ! {
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panic!()
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}
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}
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fn assignment() {
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let x;
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if true {
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x = BadDefault::default();
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} else {
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x = return;
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}
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}
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fn assignment_rev() {
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let x;
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if true {
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x = return;
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} else {
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x = BadDefault::default();
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}
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}
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fn if_then_else() {
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let _x = if true {
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BadDefault::default()
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} else {
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return;
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};
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}
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fn if_then_else_rev() {
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let _x = if true {
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return;
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} else {
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BadDefault::default()
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};
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}
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fn match_arm() {
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let _x = match Ok(BadDefault::default()) {
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Ok(v) => v,
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Err(()) => return,
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};
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}
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fn match_arm_rev() {
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let _x = match Ok(BadDefault::default()) {
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Err(()) => return,
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Ok(v) => v,
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};
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}
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fn loop_break() {
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let _x = loop {
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if false {
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break return;
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} else {
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break BadDefault::default();
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}
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};
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}
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fn loop_break_rev() {
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let _x = loop {
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if false {
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break return;
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} else {
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break BadDefault::default();
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}
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};
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}
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fn main() { }
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