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use std::fmt;
use std::os::raw::c_char;
use super::nif_interface::{ NIF_TERM };
pub fn fmt<'a>(term: NIF_TERM, f: &mut fmt::Formatter) -> Result<(), fmt::Error> {
const SIZE: usize = 1024;
let mut bytes: Vec<u8> = Vec::with_capacity(SIZE);
let mut n = 0;
for _ in 0 .. 10 {
let i = unsafe {
enif_snprintf!(bytes.as_mut_ptr() as *mut c_char,
bytes.capacity(),
b"%T\x00" as *const u8 as *const c_char,
term)
};
if i < 0 {
// Do not propagate an error, because string formatting is
// supposed to be infallible.
break;
}
n = i as usize;
if n >= bytes.capacity() {
// Bizarrely, enif_snprintf consistently underestimates the
// amount of memory it will need to write long lists. To try to
// avoid going around the loop again, double the estimate.
bytes.reserve_exact(2 * n + 1);
} else {
break;
}
}
unsafe {
bytes.set_len(n);
}
f.write_str(&String::from_utf8_lossy(&bytes))
}