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-rw-r--r--src/test/ui/const-generics/type-dependent/issue-61936.rs47
1 files changed, 47 insertions, 0 deletions
diff --git a/src/test/ui/const-generics/type-dependent/issue-61936.rs b/src/test/ui/const-generics/type-dependent/issue-61936.rs
new file mode 100644
index 000000000..7216b25f0
--- /dev/null
+++ b/src/test/ui/const-generics/type-dependent/issue-61936.rs
@@ -0,0 +1,47 @@
+// run-pass
+
+trait SliceExt<T: Clone> {
+ fn array_windows_example<'a, const N: usize>(&'a self) -> ArrayWindowsExample<'a, T, N>;
+}
+
+impl <T: Clone> SliceExt<T> for [T] {
+ fn array_windows_example<'a, const N: usize>(&'a self) -> ArrayWindowsExample<'a, T, N> {
+ ArrayWindowsExample{ idx: 0, slice: &self }
+ }
+}
+
+struct ArrayWindowsExample<'a, T, const N: usize> {
+ slice: &'a [T],
+ idx: usize,
+}
+
+impl <'a, T: Clone, const N: usize> Iterator for ArrayWindowsExample<'a, T, N> {
+ type Item = [T; N];
+ fn next(&mut self) -> Option<Self::Item> {
+ // Note: this is unsound for some `T` and not meant as an example
+ // on how to implement `ArrayWindows`.
+ let mut res = unsafe{ std::mem::zeroed() };
+ let mut ptr = &mut res as *mut [T; N] as *mut T;
+
+ for i in 0..N {
+ match self.slice[self.idx..].get(i) {
+ None => return None,
+ Some(elem) => unsafe { std::ptr::write_volatile(ptr, elem.clone())},
+ };
+ ptr = ptr.wrapping_add(1);
+ self.idx += 1;
+ }
+
+ Some(res)
+ }
+}
+
+const FOUR: usize = 4;
+
+fn main() {
+ let v: Vec<usize> = vec![0; 100];
+
+ for array in v.as_slice().array_windows_example::<FOUR>() {
+ assert_eq!(array, [0, 0, 0, 0])
+ }
+}