From: Wybo Dekker <wybo@...>
Date: 2005-06-10T07:19:45+09:00
Subject: gnu readline ruby vs. perl

I'm translating a Perl script into Ruby, but can't reproduce a readline 
action. I made two, hopefully equivalent, test scripts in Perl and Ruby, 
but they behave differently.

Here's my Perl script: 

    #!/usr/bin/perl
    use Term::ReadLine;
    
    # count lines in stdin (the mail message):
    $n=0; while (<>) { $n++ }
    print "$n lines\n";
    
    my $term=new Term::ReadLine 'vpp';
    $term->readline("type return to quit: ")

And here the test run:

    $ echo test |readlineperl
    1 lines
    type return to quit: 
    $ 

Now the Ruby version:

    #!/usr/bin/env ruby
    
    require 'readline'
    include Readline
    
    # count lines in stdin (the mail message):
    n=0; while gets: n+=1 end
    puts "#{n} lines"
    
    readline("type return to quit: ")

Its test run does not exit with a return - it needs ctrl-C:

    $ echo test |readlineruby
    1 lines
    type return to quit: 
    ./readlineruby:10:in `readline': Interrupt
            from ./readlineruby:10
    $

Is this a bug? Or a missing feature, like Readline.new? 

-- 
Wybo