22 lines
556 B
Rust
22 lines
556 B
Rust
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#![feature(const_generics)]
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#![allow(incomplete_features)]
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use std::ffi::{CStr, CString};
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unsafe fn unsafely_do_the_thing<const F: fn(&CStr) -> usize>(ptr: *const i8) -> usize {
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//~^ ERROR: using function pointers as const generic parameters is forbidden
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F(CStr::from_ptr(ptr))
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}
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fn safely_do_the_thing(s: &CStr) -> usize {
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s.to_bytes().len()
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}
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fn main() {
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let baguette = CString::new("baguette").unwrap();
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let ptr = baguette.as_ptr();
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println!("{}", unsafe {
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unsafely_do_the_thing::<safely_do_the_thing>(ptr)
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});
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}
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