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extern crate unicode_names2;
use std::char;
// Count how many code points have names in the standard.
//
// This does a full naive scan of all valid codepoints, and still only
// takes milliseconds to complete. Specifically, with optimisations,
// it takes about 14ms to run, meaning ~12ns per look-up (only 2048
// out of 1114111 fail the from_u32 check).
//
// NB. this is not actually doing any work to compute the name, just
// checking it exists, which is why it can be so efficient.
fn main() {
let number = (0u32..0x10FFFF)
.filter(|x| {
char::from_u32(*x).map_or(false, |c| unicode_names2::name(c).is_some())
})
.count();
println!("there are {} named code points", number)
}
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