diff options
| -rw-r--r-- | rust/src/lambda.rs | 14 |
1 files changed, 8 insertions, 6 deletions
diff --git a/rust/src/lambda.rs b/rust/src/lambda.rs index 3a8372b..8ac3e46 100644 --- a/rust/src/lambda.rs +++ b/rust/src/lambda.rs @@ -117,7 +117,7 @@ pub fn generate_expr(size: u32, runner: &mut TestRunner) -> Value { 6 => simple_lambda().new_tree(runner).unwrap().current(), 7 => app_to_lambda().new_tree(runner).unwrap().current(), 8 => multi_app().new_tree(runner).unwrap().current(), - 9 => any::<u16>() + 9 => any::<u32>() .prop_flat_map(gen_terms) .new_tree(runner) .unwrap() @@ -162,14 +162,16 @@ fn app_to_lambda() -> impl Strategy<Value = Value> { (lam, arg).prop_map(|(l, a)| Value::App(Box::new(l), Box::new(a))) } -fn pairing(k: u16) -> (u16, u16) { - let a = ((((8 * (k as u32) + 1) as f32).sqrt() - 1.0) / 2.0).floor(); +/// Cantor pairing function +/// See https://en.wikipedia.org/wiki/Pairing_function +fn pairing(k: u32) -> (u32, u32) { + let a = ((((8 * (k as u64) + 1) as f64).sqrt() - 1.0) / 2.0).floor(); let b = (a * (a + 1.0)) / 2.0; - let n = (k as f32) - b; - (n as u16, (a - n) as u16) + let n = (k as f64) - b; + (n as u32, (a - n) as u32) } -fn gen_terms(u: u16) -> impl Strategy<Value = Value> { +fn gen_terms(u: u32) -> impl Strategy<Value = Value> { if u % 2 != 0 { let j = (u - 1) / 2; if j % 2 == 0 { |