rust/tests/ui/consts/const-block-item-macro-codegen.rs
2023-01-11 09:32:08 +00:00

41 lines
837 B
Rust

// run-pass
#![allow(dead_code)]
// General test that function items in static blocks
// can be generated with a macro.
struct MyType {
desc: &'static str,
data: usize,
code: fn(usize, usize) -> usize
}
impl MyType {
fn eval(&self, a: usize) -> usize {
(self.code)(self.data, a)
}
}
macro_rules! codegen {
($e:expr, $v:expr) => {
{
fn generated(a: usize, b: usize) -> usize {
a - ($e * b)
}
MyType {
desc: "test",
data: $v,
code: generated
}
}
}
}
static GENERATED_CODE_1: MyType = codegen!(2, 100);
static GENERATED_CODE_2: MyType = codegen!(5, 1000);
pub fn main() {
assert_eq!(GENERATED_CODE_1.eval(10), 80);
assert_eq!(GENERATED_CODE_2.eval(100), 500);
}