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//! Counts the number of records in a GFF file.
//!
//! Assuming the input does not have a FASTA section, the result matches the output of `grep
//! --count --invert-match '^#' <src>`.

use std::{
    env,
    fs::File,
    io::{self, BufReader},
};

use noodles_gff as gff;

fn main() -> io::Result<()> {
    let src = env::args().nth(1).expect("missing src");

    let mut reader = File::open(src).map(BufReader::new).map(gff::Reader::new)?;
    let mut n = 0;

    for result in reader.records() {
        let _ = result?;
        n += 1;
    }

    println!("{n}");

    Ok(())
}