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-rw-r--r--src/test/ui/unboxed-closures/unboxed-closures-infer-recursive-fn.rs45
1 files changed, 0 insertions, 45 deletions
diff --git a/src/test/ui/unboxed-closures/unboxed-closures-infer-recursive-fn.rs b/src/test/ui/unboxed-closures/unboxed-closures-infer-recursive-fn.rs
deleted file mode 100644
index a0fbbafe2..000000000
--- a/src/test/ui/unboxed-closures/unboxed-closures-infer-recursive-fn.rs
+++ /dev/null
@@ -1,45 +0,0 @@
-// run-pass
-#![feature(fn_traits, unboxed_closures)]
-
-use std::marker::PhantomData;
-
-// Test that we are able to infer a suitable kind for a "recursive"
-// closure. As far as I can tell, coding up a recursive closure
-// requires the good ol' [Y Combinator].
-//
-// [Y Combinator]: https://en.wikipedia.org/wiki/Fixed-point_combinator#Y_combinator
-
-struct YCombinator<F,A,R> {
- func: F,
- marker: PhantomData<(A,R)>,
-}
-
-impl<F,A,R> YCombinator<F,A,R> {
- fn new(f: F) -> YCombinator<F,A,R> {
- YCombinator { func: f, marker: PhantomData }
- }
-}
-
-impl<A,R,F : Fn(&dyn Fn(A) -> R, A) -> R> Fn<(A,)> for YCombinator<F,A,R> {
- extern "rust-call" fn call(&self, (arg,): (A,)) -> R {
- (self.func)(self, arg)
- }
-}
-
-impl<A,R,F : Fn(&dyn Fn(A) -> R, A) -> R> FnMut<(A,)> for YCombinator<F,A,R> {
- extern "rust-call" fn call_mut(&mut self, args: (A,)) -> R { self.call(args) }
-}
-
-impl<A,R,F : Fn(&dyn Fn(A) -> R, A) -> R> FnOnce<(A,)> for YCombinator<F,A,R> {
- type Output = R;
- extern "rust-call" fn call_once(self, args: (A,)) -> R { self.call(args) }
-}
-
-fn main() {
- let factorial = |recur: &dyn Fn(u32) -> u32, arg: u32| -> u32 {
- if arg == 0 {1} else {arg * recur(arg-1)}
- };
- let factorial: YCombinator<_,u32,u32> = YCombinator::new(factorial);
- let r = factorial(10);
- assert_eq!(3628800, r);
-}