ReadLine Async

#!usr/bin/perl -w

use warnings;
use strict;
use feature qw(state);
use Term::ReadKey qw(ReadKey);

sub readLine {
    my $c;
    state $buffer = "";
    while($c = ReadKey(-1)) {
        print $c;
        if($c eq chr(8) && length($buffer)) {
            $buffer = substr($buffer, 0, length($buffer) -1);
            next;
        }
        $buffer .= $c;
        if($c eq "\r") {
            my $b = $buffer;
            $buffer = "";
            return $b;
        }
    }
    return undef;
}

while(1) {
    my $i = readLine();
    print $i if($i);
}