src/test/ui/const-generics/issues/issue-72352.rs

   1 // revisions: full min
   2 #![cfg_attr(full, feature(const_generics))]
   3 #![cfg_attr(full, allow(incomplete_features))]
   4
   5 use std::ffi::{CStr, CString};
   6
   7 unsafe fn unsafely_do_the_thing<const F: fn(&CStr) -> usize>(ptr: *const i8) -> usize {
   8     //~^ ERROR: using function pointers as const generic parameters is forbidden
   9     F(CStr::from_ptr(ptr))
  10 }
  11
  12 fn safely_do_the_thing(s: &CStr) -> usize {
  13     s.to_bytes().len()
  14 }
  15
  16 fn main() {
  17     let baguette = CString::new("baguette").unwrap();
  18     let ptr = baguette.as_ptr();
  19     println!("{}", unsafe {
  20         unsafely_do_the_thing::<safely_do_the_thing>(ptr)
  21     });
  22 }