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//@ revisions: explicit implicit
//@ run-pass
#![feature(deref_patterns)]
#![allow(incomplete_features)]
use std::rc::Rc;
#[cfg(explicit)]
fn simple_vec(vec: Vec<u32>) -> u32 {
match vec {
deref!([]) => 100,
deref!([x]) if x == 4 => x + 4,
deref!([x]) => x,
deref!([1, x]) => x + 200,
deref!(ref slice) => slice.iter().sum(),
}
}
#[cfg(implicit)]
fn simple_vec(vec: Vec<u32>) -> u32 {
match vec {
[] => 100,
[x] if x == 4 => x + 4,
[x] => x,
[1, x] => x + 200,
deref!(ref slice) => slice.iter().sum(),
}
}
#[cfg(explicit)]
fn nested_vec(vecvec: Vec<Vec<u32>>) -> u32 {
match vecvec {
deref!([]) => 0,
deref!([deref!([x])]) => x,
deref!([deref!([0, x]) | deref!([1, x])]) => x,
deref!([ref x]) => x.iter().sum(),
deref!([deref!([]), deref!([1, x, y])]) => y - x,
_ => 2000,
}
}
#[cfg(implicit)]
fn nested_vec(vecvec: Vec<Vec<u32>>) -> u32 {
match vecvec {
[] => 0,
[[x]] => x,
[[0, x] | [1, x]] => x,
[ref x] => x.iter().sum(),
[[], [1, x, y]] => y - x,
_ => 2000,
}
}
#[cfg(explicit)]
fn ref_mut(val: u32) -> u32 {
let mut b = vec![0u32];
match &mut b {
deref!([_x]) if false => unreachable!(),
deref!([x]) => {
*x = val;
}
_ => unreachable!(),
}
let deref!([x]) = &b else { unreachable!() };
*x
}
#[cfg(implicit)]
fn ref_mut(val: u32) -> u32 {
let mut b = vec![0u32];
match &mut b {
[_x] if false => unreachable!(),
[x] => {
*x = val;
}
_ => unreachable!(),
}
let [x] = &b else { unreachable!() };
*x
}
#[cfg(explicit)]
#[rustfmt::skip]
fn or_and_guard(tuple: (u32, u32)) -> u32 {
let mut sum = 0;
let b = Rc::new(tuple);
match b {
deref!((x, _) | (_, x)) if { sum += x; false } => {},
_ => {},
}
sum
}
#[cfg(implicit)]
#[rustfmt::skip]
fn or_and_guard(tuple: (u32, u32)) -> u32 {
let mut sum = 0;
let b = Rc::new(tuple);
match b {
(x, _) | (_, x) if { sum += x; false } => {},
_ => {},
}
sum
}
fn main() {
assert_eq!(simple_vec(vec![1]), 1);
assert_eq!(simple_vec(vec![1, 2]), 202);
assert_eq!(simple_vec(vec![1, 2, 3]), 6);
assert_eq!(simple_vec(vec![4]), 8);
assert_eq!(nested_vec(vec![vec![0, 42]]), 42);
assert_eq!(nested_vec(vec![vec![1, 42]]), 42);
assert_eq!(nested_vec(vec![vec![1, 2, 3]]), 6);
assert_eq!(nested_vec(vec![vec![], vec![1, 2, 3]]), 1);
assert_eq!(ref_mut(42), 42);
assert_eq!(or_and_guard((10, 32)), 42);
}
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