| // build-pass (FIXME(62277): could be check-pass?) |
| |
| #![feature(const_fn)] |
| |
| struct Foo<T>(T); |
| struct Bar<T> { x: T } |
| struct W(f32); |
| struct A { a: f32 } |
| |
| #[allow(redundant_semicolons)] |
| const fn basics((a,): (f32,)) -> f32 { |
| // Deferred assignment: |
| let b: f32; |
| b = a + 1.0; |
| |
| // Immediate assignment: |
| let c: f32 = b + 1.0; |
| |
| // Mutables: |
| let mut d: f32 = c + 1.0; |
| d = d + 1.0; |
| // +4 so far. |
| |
| // No effect statements work: |
| ; ; |
| 1; |
| |
| // Array projection |
| let mut arr: [f32; 1] = [0.0]; |
| arr[0] = 1.0; |
| d = d + arr[0]; |
| // +5 |
| |
| // Field projection: |
| let mut foo: Foo<f32> = Foo(0.0); |
| let mut bar: Bar<f32> = Bar { x: 0.0 }; |
| foo.0 = 1.0; |
| bar.x = 1.0; |
| d = d + foo.0 + bar.x; |
| // +7 |
| |
| // Array + Field projection: |
| let mut arr: [Foo<f32>; 1] = [Foo(0.0)]; |
| arr[0].0 = 1.0; |
| d = d + arr[0].0; |
| let mut arr: [Bar<f32>; 1] = [Bar { x: 0.0 }]; |
| arr[0].x = 1.0; |
| d = d + arr[0].x; |
| // +9 |
| |
| // Field + Array projection: |
| let mut arr: Foo<[f32; 1]> = Foo([0.0]); |
| (arr.0)[0] = 1.0; |
| d = d + (arr.0)[0]; |
| let mut arr: Bar<[f32; 1]> = Bar { x: [0.0] }; |
| arr.x[0] = 1.0; |
| d = d + arr.x[0]; |
| // +11 |
| |
| d |
| } |
| |
| const fn add_assign(W(a): W) -> f32 { |
| // Mutables: |
| let mut d: f32 = a + 1.0; |
| d += 1.0; |
| // +2 so far. |
| |
| // Array projection |
| let mut arr: [f32; 1] = [0.0]; |
| arr[0] += 1.0; |
| d += arr[0]; |
| // +3 |
| |
| // Field projection: |
| let mut foo: Foo<f32> = Foo(0.0); |
| let mut bar: Bar<f32> = Bar { x: 0.0 }; |
| foo.0 += 1.0; |
| bar.x += 1.0; |
| d += foo.0 + bar.x; |
| // +5 |
| |
| // Array + Field projection: |
| let mut arr: [Foo<f32>; 1] = [Foo(0.0)]; |
| arr[0].0 += 1.0; |
| d += arr[0].0; |
| let mut arr: [Bar<f32>; 1] = [Bar { x: 0.0 }]; |
| arr[0].x += 1.0; |
| d += arr[0].x; |
| // +7 |
| |
| // Field + Array projection: |
| let mut arr: Foo<[f32; 1]> = Foo([0.0]); |
| (arr.0)[0] += 1.0; |
| d += (arr.0)[0]; |
| let mut arr: Bar<[f32; 1]> = Bar { x: [0.0] }; |
| arr.x[0] += 1.0; |
| d += arr.x[0]; |
| // +9 |
| |
| d |
| } |
| |
| const fn mul_assign(A { a }: A) -> f32 { |
| // Mutables: |
| let mut d: f32 = a + 1.0; |
| d *= 2.0; |
| // 2^1 * (a + 1) |
| |
| // Array projection |
| let mut arr: [f32; 1] = [1.0]; |
| arr[0] *= 2.0; |
| d *= arr[0]; |
| // 2^2 * (a + 1) |
| |
| // Field projection: |
| let mut foo: Foo<f32> = Foo(1.0); |
| let mut bar: Bar<f32> = Bar { x: 1.0 }; |
| foo.0 *= 2.0; |
| bar.x *= 2.0; |
| d *= foo.0 + bar.x; |
| // 2^4 * (a + 1) |
| |
| // Array + Field projection: |
| let mut arr: [Foo<f32>; 1] = [Foo(1.0)]; |
| arr[0].0 *= 2.0; |
| d *= arr[0].0; |
| let mut arr: [Bar<f32>; 1] = [Bar { x: 1.0 }]; |
| arr[0].x *= 2.0; |
| d *= arr[0].x; |
| // 2^6 * (a + 1) |
| |
| // Field + Array projection: |
| let mut arr: Foo<[f32; 1]> = Foo([1.0]); |
| (arr.0)[0] *= 2.0; |
| d *= (arr.0)[0]; |
| let mut arr: Bar<[f32; 1]> = Bar { x: [1.0] }; |
| arr.x[0] *= 2.0; |
| d *= arr.x[0]; |
| // 2^8 * (a + 1) |
| |
| d |
| } |
| |
| const fn div_assign(a: [f32; 1]) -> f32 { |
| let a = a[0]; |
| // Mutables: |
| let mut d: f32 = 1024.0 * a; |
| d /= 2.0; |
| // 512 |
| |
| // Array projection |
| let mut arr: [f32; 1] = [4.0]; |
| arr[0] /= 2.0; |
| d /= arr[0]; |
| // 256 |
| |
| // Field projection: |
| let mut foo: Foo<f32> = Foo(4.0); |
| let mut bar: Bar<f32> = Bar { x: 4.0 }; |
| foo.0 /= 2.0; |
| bar.x /= 2.0; |
| d /= foo.0; |
| d /= bar.x; |
| // 64 |
| |
| // Array + Field projection: |
| let mut arr: [Foo<f32>; 1] = [Foo(4.0)]; |
| arr[0].0 /= 2.0; |
| d /= arr[0].0; |
| let mut arr: [Bar<f32>; 1] = [Bar { x: 4.0 }]; |
| arr[0].x /= 2.0; |
| d /= arr[0].x; |
| // 16 |
| |
| // Field + Array projection: |
| let mut arr: Foo<[f32; 1]> = Foo([4.0]); |
| (arr.0)[0] /= 2.0; |
| d /= (arr.0)[0]; |
| let mut arr: Bar<[f32; 1]> = Bar { x: [4.0] }; |
| arr.x[0] /= 2.0; |
| d /= arr.x[0]; |
| // 4 |
| |
| d |
| } |
| |
| const fn rem_assign(W(a): W) -> f32 { |
| // Mutables: |
| let mut d: f32 = a; |
| d %= 10.0; |
| d += 10.0; |
| |
| // Array projection |
| let mut arr: [f32; 1] = [3.0]; |
| arr[0] %= 2.0; |
| d %= 9.0 + arr[0]; |
| d += 10.0; |
| |
| // Field projection: |
| let mut foo: Foo<f32> = Foo(5.0); |
| let mut bar: Bar<f32> = Bar { x: 7.0 }; |
| foo.0 %= 2.0; |
| bar.x %= 2.0; |
| d %= 8.0 + foo.0 + bar.x; |
| d += 10.0; |
| |
| // Array + Field projection: |
| let mut arr: [Foo<f32>; 1] = [Foo(4.0)]; |
| arr[0].0 %= 3.0; |
| d %= 9.0 + arr[0].0; |
| d += 10.0; |
| let mut arr: [Bar<f32>; 1] = [Bar { x: 7.0 }]; |
| arr[0].x %= 3.0; |
| d %= 9.0 + arr[0].x; |
| d += 10.0; |
| |
| // Field + Array projection: |
| let mut arr: Foo<[f32; 1]> = Foo([6.0]); |
| (arr.0)[0] %= 5.0; |
| d %= 9.0 + (arr.0)[0]; |
| let mut arr: Bar<[f32; 1]> = Bar { x: [11.0] }; |
| arr.x[0] %= 5.0; |
| d %= 9.0 + arr.x[0]; |
| |
| d |
| } |
| |
| const fn sub_assign(W(a): W) -> f32 { |
| // Mutables: |
| let mut d: f32 = a; |
| d -= 1.0; |
| |
| // Array projection |
| let mut arr: [f32; 1] = [2.0]; |
| arr[0] -= 1.0; |
| d -= arr[0]; |
| |
| // Field projection: |
| let mut foo: Foo<f32> = Foo(2.0); |
| let mut bar: Bar<f32> = Bar { x: 2.0 }; |
| foo.0 -= 1.0; |
| bar.x -= 1.0; |
| d -= foo.0 + bar.x; |
| |
| // Array + Field projection: |
| let mut arr: [Foo<f32>; 1] = [Foo(2.0)]; |
| arr[0].0 -= 1.0; |
| d -= arr[0].0; |
| let mut arr: [Bar<f32>; 1] = [Bar { x: 2.0 }]; |
| arr[0].x -= 1.0; |
| d -= arr[0].x; |
| |
| // Field + Array projection: |
| let mut arr: Foo<[f32; 1]> = Foo([2.0]); |
| (arr.0)[0] -= 1.0; |
| d -= (arr.0)[0]; |
| let mut arr: Bar<[f32; 1]> = Bar { x: [2.0] }; |
| arr.x[0] -= 1.0; |
| d -= arr.x[0]; |
| |
| d |
| } |
| |
| macro_rules! test { |
| ($c:ident, $e:expr, $r:expr) => { |
| const $c: f32 = $e; |
| assert_eq!($c, $r); |
| assert_eq!($e, $r); |
| } |
| } |
| |
| fn main() { |
| test!(BASICS, basics((2.0,)), 13.0); |
| test!(ADD, add_assign(W(1.0)), 10.0); |
| test!(MUL, mul_assign(A { a: 0.0 }), 256.0); |
| test!(DIV, div_assign([1.0]), 4.0); |
| test!(REM, rem_assign(W(5.0)), 5.0); |
| test!(SUB, sub_assign(W(8.0)), 0.0); |
| } |