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// ICE argument to function with "rust-call" ABI is not a tuple
// issue: rust-lang/rust#81974
#![feature(unboxed_closures)]
#![feature(fn_traits)]
use std::collections::HashMap;
use std::hash::Hash;
struct CachedFun<A, B> {
cache: HashMap<A, B>,
fun: fn(&mut CachedFun<A, B>, A) -> B,
}
impl<A: Eq + Hash, B> CachedFun<A, B> {
fn new(fun: fn(&mut Self, A) -> B) -> Self {
CachedFun {
cache: HashMap::new(),
fun,
}
}
}
impl<A, B> FnOnce<A> for CachedFun<A, B>
//~^ ERROR type parameter to bare `FnOnce` trait must be a tuple
where
A: Eq + Hash + Clone,
B: Clone,
{
type Output = B;
extern "rust-call" fn call_once(mut self, a: A) -> Self::Output {
//~^ ERROR functions with the "rust-call" ABI must take a single non-self tuple argument
self.call_mut(a)
//~^ ERROR `A` is not a tuple
}
}
impl<A, B> FnMut<A> for CachedFun<A, B>
//~^ ERROR type parameter to bare `FnMut` trait must be a tuple
where
A: Eq + Hash + Clone,
B: Clone,
{
extern "rust-call" fn call_mut(&mut self, a: A) -> Self::Output {
//~^ ERROR functions with the "rust-call" ABI must take a single non-self tuple argument
self.cache.get(&a).map(|a| a.clone()).unwrap_or_else(|| {
let b = (self.fun)(self, a.clone());
self.cache.insert(a, b.clone());
b
})
}
}
fn main() -> () {
let pesce = |y: &mut CachedFun<i32, i32>, x| x + 1;
let cachedcoso = CachedFun::new(pesce);
cachedcoso.call_once(1);
//~^ ERROR `i32` is not a tuple
}
|
