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diff --git a/src/test/ui/const-generics/issue-97007.rs b/src/test/ui/const-generics/issue-97007.rs
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+// check-pass
+
+#![feature(adt_const_params, generic_const_exprs)]
+#![allow(incomplete_features)]
+
+mod lib {
+ const N_ISLANDS: usize = 4;
+ const N_BRIDGES: usize = 7;
+ const BRIDGES: [(usize, usize); 7] = [(0, 1), (0, 1), (0, 2), (0, 3), (0, 3), (1, 2), (2, 3)];
+
+ pub type Matrix = [[usize; N_ISLANDS]; N_ISLANDS];
+
+ const EMPTY_MATRIX: Matrix = [[0; N_ISLANDS]; N_ISLANDS];
+
+ const fn build(mut matrix: Matrix, (to, from): (usize, usize)) -> Matrix {
+ matrix[to][from] += 1;
+ matrix[from][to] += 1;
+ matrix
+ }
+
+ pub const fn walk(mut matrix: Matrix, from: usize, to: usize) -> Matrix {
+ matrix[from][to] -= 1;
+ matrix[to][from] -= 1;
+ matrix
+ }
+
+ const fn to_matrix(bridges: [(usize, usize); N_BRIDGES]) -> Matrix {
+ let matrix = EMPTY_MATRIX;
+
+ let matrix = build(matrix, bridges[0]);
+ let matrix = build(matrix, bridges[1]);
+ let matrix = build(matrix, bridges[2]);
+ let matrix = build(matrix, bridges[3]);
+ let matrix = build(matrix, bridges[4]);
+ let matrix = build(matrix, bridges[5]);
+ let matrix = build(matrix, bridges[6]);
+
+ matrix
+ }
+
+ const BRIDGE_MATRIX: [[usize; N_ISLANDS]; N_ISLANDS] = to_matrix(BRIDGES);
+
+ pub struct Walk<const CURRENT: usize, const REMAINING: Matrix> {
+ _p: (),
+ }
+
+ impl Walk<0, BRIDGE_MATRIX> {
+ pub const fn new() -> Self {
+ Self { _p: () }
+ }
+ }
+
+ impl<const CURRENT: usize, const REMAINING: Matrix> Walk<CURRENT, REMAINING> {
+ pub fn proceed_to<const NEXT: usize>(
+ self,
+ ) -> Walk<NEXT, { walk(REMAINING, CURRENT, NEXT) }> {
+ Walk { _p: () }
+ }
+ }
+
+ pub struct Trophy {
+ _p: (),
+ }
+
+ impl<const CURRENT: usize> Walk<CURRENT, EMPTY_MATRIX> {
+ pub fn collect_prize(self) -> Trophy {
+ Trophy { _p: () }
+ }
+ }
+}
+
+pub use lib::{Trophy, Walk};
+
+fn main() {
+ // Example, taking the first step
+ let _ = Walk::new().proceed_to::<1>();
+
+ // Don't be so eager to collect the trophy
+ // let trophy = Walk::new()
+ // .proceed_to::<1>()
+ // .proceed_to::<0>()
+ // .collect_prize();
+
+ // Can't just make a Trophy out of thin air, you must earn it
+ // let trophy: Trophy = Trophy { _p: () };
+
+ // Can you collect the Trophy?
+}