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//@ [coq,fstar] aeneas-args=-use-fuel
//@ [lean] subdir=Demo
#![allow(clippy::needless_lifetimes)]
/* Simple functions */
pub fn choose<'a, T>(b: bool, x: &'a mut T, y: &'a mut T) -> &'a mut T {
if b {
x
} else {
y
}
}
pub fn mul2_add1(x: u32) -> u32 {
(x + x) + 1
}
pub fn use_mul2_add1(x: u32, y: u32) -> u32 {
mul2_add1(x) + y
}
pub fn incr<'a>(x: &'a mut u32) {
*x += 1;
}
pub fn use_incr() {
let mut x = 0;
incr(&mut x);
incr(&mut x);
incr(&mut x);
}
/* Recursion, loops */
pub enum CList<T> {
CCons(T, Box<CList<T>>),
CNil,
}
pub fn list_nth<'a, T>(l: &'a CList<T>, i: u32) -> &'a T {
match l {
CList::CCons(x, tl) => {
if i == 0 {
x
} else {
list_nth(tl, i - 1)
}
}
CList::CNil => {
panic!()
}
}
}
pub fn list_nth_mut<'a, T>(l: &'a mut CList<T>, i: u32) -> &'a mut T {
match l {
CList::CCons(x, tl) => {
if i == 0 {
x
} else {
list_nth_mut(tl, i - 1)
}
}
CList::CNil => {
panic!()
}
}
}
pub fn list_nth_mut1<'a, T>(mut l: &'a mut CList<T>, mut i: u32) -> &'a mut T {
while let CList::CCons(x, tl) = l {
if i == 0 {
return x;
}
i -= 1;
l = tl;
}
panic!()
}
pub fn i32_id(i: i32) -> i32 {
if i == 0 {
0
} else {
i32_id(i - 1) + 1
}
}
pub fn list_tail<'a, T>(l: &'a mut CList<T>) -> &'a mut CList<T> {
match l {
CList::CCons(_, tl) => list_tail(tl),
CList::CNil => l,
}
}
/* Traits */
pub trait Counter {
fn incr(&mut self) -> usize;
}
impl Counter for usize {
fn incr(&mut self) -> usize {
let x = *self;
*self += 1;
x
}
}
pub fn use_counter<'a, T: Counter>(cnt: &'a mut T) -> usize {
cnt.incr()
}
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