#![feature(exclusive_range_pattern)] #![allow(overlapping_range_endpoints)] #![deny(unreachable_patterns)] macro_rules! m { ($s:expr, $($t:tt)+) => { match $s { $($t)+ => {} } } } macro_rules! test_int { ($s:expr, $min:path, $max:path) => { m!($s, $min..=$max); m!($s, $min..5 | 5..=$max); m!($s, $min..=4 | 5..=$max); m!($s, $min..$max | $max); m!(($s, true), ($min..5, true) | (5..=$max, true) | ($min..=$max, false)); } } fn main() { test_int!(0u8, u8::MIN, u8::MAX); test_int!(0u16, u16::MIN, u16::MAX); test_int!(0u32, u32::MIN, u32::MAX); test_int!(0u64, u64::MIN, u64::MAX); test_int!(0u128, u128::MIN, u128::MAX); test_int!(0i8, i8::MIN, i8::MAX); test_int!(0i16, i16::MIN, i16::MAX); test_int!(0i32, i32::MIN, i32::MAX); test_int!(0i64, i64::MIN, i64::MAX); test_int!(0i128, i128::MIN, i128::MAX); m!('a', '\u{0}'..=char::MAX); m!('a', '\u{0}'..='\u{10_FFFF}'); // We can get away with just covering the following two ranges, which correspond to all valid // Unicode Scalar Values. m!('a', '\u{0}'..='\u{D7FF}' | '\u{E000}'..=char::MAX); m!('a', '\u{0}'..'\u{D7FF}' | '\u{D7FF}' | '\u{E000}'..=char::MAX); let 0..=255 = 0u8; let -128..=127 = 0i8; let -2147483648..=2147483647 = 0i32; let '\u{0000}'..='\u{10FFFF}' = 'v'; // Almost exhaustive m!(0u8, 0..255); //~ ERROR non-exhaustive patterns m!(0u8, 0..=254); //~ ERROR non-exhaustive patterns m!(0u8, 1..=255); //~ ERROR non-exhaustive patterns m!(0u8, 0..42 | 43..=255); //~ ERROR non-exhaustive patterns m!(0i8, -128..127); //~ ERROR non-exhaustive patterns m!(0i8, -128..=126); //~ ERROR non-exhaustive patterns m!(0i8, -127..=127); //~ ERROR non-exhaustive patterns match 0i8 { //~ ERROR non-exhaustive patterns i8::MIN ..= -1 => {} 1 ..= i8::MAX => {} } const ALMOST_MAX: u128 = u128::MAX - 1; m!(0u128, 0..=ALMOST_MAX); //~ ERROR non-exhaustive patterns m!(0u128, 0..=4); //~ ERROR non-exhaustive patterns m!(0u128, 1..=u128::MAX); //~ ERROR non-exhaustive patterns // More complicatedly (non-)exhaustive match 0u8 { 0 ..= 30 => {} 20 ..= 70 => {} 50 ..= 255 => {} } match (0u8, true) { //~ ERROR non-exhaustive patterns (0 ..= 125, false) => {} (128 ..= 255, false) => {} (0 ..= 255, true) => {} } match (0u8, true) { // ok (0 ..= 125, false) => {} (128 ..= 255, false) => {} (0 ..= 255, true) => {} (125 .. 128, false) => {} } match (true, 0u8) { (true, 0 ..= 255) => {} (false, 0 ..= 125) => {} (false, 128 ..= 255) => {} (false, 125 .. 128) => {} } match Some(0u8) { None => {} Some(0 ..= 125) => {} Some(128 ..= 255) => {} Some(125 .. 128) => {} } const FOO: u8 = 41; const BAR: &u8 = &42; match &0u8 { 0..41 => {} &FOO => {} BAR => {} 43..=255 => {} } }