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#![allow(dead_code)]
#![deny(unreachable_patterns)]
use self::Direction::{North, East, South, West};
#[derive(PartialEq, Eq)]
struct NewBool(bool);
#[derive(PartialEq, Eq)]
enum Direction {
North,
East,
South,
West
}
const TRUE_TRUE: (bool, bool) = (true, true);
fn unreachable_1() {
match (true, false) {
TRUE_TRUE => (),
(false, false) => (),
(false, true) => (),
(true, false) => (),
(true, true) => ()
//~^ ERROR unreachable pattern
}
}
const NONE: Option<Direction> = None;
const EAST: Direction = East;
fn unreachable_2() {
match Some(Some(North)) {
Some(NONE) => (),
Some(Some(North)) => (),
Some(Some(EAST)) => (),
Some(Some(South)) => (),
Some(Some(West)) => (),
Some(Some(East)) => (),
//~^ ERROR unreachable pattern
None => ()
}
}
const NEW_FALSE: NewBool = NewBool(false);
struct Foo {
bar: Option<Direction>,
baz: NewBool
}
fn unreachable_3() {
match (Foo { bar: Some(EAST), baz: NewBool(true) }) {
Foo { bar: None, baz: NewBool(true) } => (),
Foo { bar: _, baz: NEW_FALSE } => (),
Foo { bar: Some(West), baz: NewBool(true) } => (),
Foo { bar: Some(South), .. } => (),
Foo { bar: Some(EAST), .. } => (),
Foo { bar: Some(North), baz: NewBool(true) } => (),
Foo { bar: Some(EAST), baz: NewBool(false) } => ()
//~^ ERROR unreachable pattern
}
}
fn main() {
unreachable_1();
unreachable_2();
unreachable_3();
}
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