POSIX wc (word count)

wc.rs

extern mod extra;
use extra::getopts::*;
 
pub struct Total {
    lines: uint,
    words: uint,
    chars: uint,
    bytes: uint
}
 
pub struct Shown {
    lines: bool,
    words: bool,
    chars: bool,
    bytes: bool,
    filename: bool
}
 
fn count(filename: &str) -> Total {
    let mut total = Total{
        lines: 0, 
        words: 0, 
        chars: 0, 
        bytes: 0
    };
 
    let s = match std::io::read_whole_file_str(&Path(filename)) {
        std::result::Err(f) => fail!(f),
        std::result::Ok(s) => s
    };
 
    for ch in s.iter() {
        if ch == '\n' {
            total.lines += 1;
        }
        if std::char::is_whitespace(ch) {
            total.words += 1;
        }
    }
 
    total.chars = s.char_len();
    total.bytes = s.len();
 
    return total;
}
 
fn print_count(filename: &str, show: &Shown) -> Total {
    let total = count(filename);
    print_total(filename, show, total);
    return total;
}
 
fn print_total(filename: &str, show: &Shown, total: Total) {
    if show.lines {
        print(fmt!("%d ", total.lines as int));
    }
    if show.words {
        print(fmt!("%d ", total.words as int));
    }
    if show.chars {
        print(fmt!("%d ", total.chars as int));
    } else if show.bytes {
        print(fmt!("%d ", total.bytes as int));
    }
 
    if show.filename {
        println(filename);
    } else {
        println("");
    }
}
 
fn main() {
    let program_and_args = std::os::args();
    let program = program_and_args[0].clone();
    let opts = [
        optflag("c"), optflag("bytes"),
        optflag("l"), optflag("lines"),
        optflag("m"), optflag("chars"),
        optflag("w"), optflag("words"),
        optflag("h"), optflag("help")
    ];
 
    let mut show = Shown{
        lines: false, 
        words: false, 
        chars: false, 
        bytes: false,
        filename: true
    };
    let mut total = Total{
        lines: 0, 
        words: 0, 
        chars: 0, 
        bytes: 0
    };
 
    let args = program_and_args.tail();
    let matches = match getopts(args, opts) {
        std::result::Err(f) => fail!(f.to_err_msg()),
        std::result::Ok(m) => m
    };
 
    if matches.opt_present("h") || 
       matches.opt_present("help") {
        println(fmt!("Usage: %s [-clmw] [FILE ...]", program));
        println("\t-c | --bytes    Print bytes");
        println("\t-m | --chars    Print chars");
        println("\t-w | --words    Print words");
        println("\t-l | --lines    Print lines");
        std::os::set_exit_status(1);
        return;
    }
 
    // HACK: getopt should provide this
    let optcount = args.len() - matches.free.len();
    if optcount == 0 {
        show.lines = true; 
        show.words = true;
        show.bytes = true;
    }
 
    if matches.opt_present("l") || 
       matches.opt_present("lines") {
        show.lines = true;
    }
    if matches.opt_present("w") || 
       matches.opt_present("words") {
        show.words = true;
    }
    if matches.opt_present("m") || 
       matches.opt_present("chars") {
        show.chars = true;
    } else if matches.opt_present("c") || 
              matches.opt_present("bytes") {
        show.bytes = true;
    }
 
    if matches.free.len() == 0 {
        show.filename = false;
        print_count("/dev/stdin", &show);
        return;
    }
 
    for arg in matches.free.iter() {
        let subtotal;
        let filename = arg.to_str();
        if filename == ~"-" {
            subtotal = print_count("/dev/stdin", &show);
        } else {
            subtotal = print_count(filename, &show);
        }
        total.lines += subtotal.lines;
        total.words += subtotal.words;
        total.chars += subtotal.chars;
        total.bytes += subtotal.bytes;
    }
 
    show.filename = false;
    print_total("total", &show, total);
}