Alex, Thank you very much for your explanation. I have one question about your response. I don't dispute your statement: > Which in Ruby is better written as: > > puts "Invalid filename entered: #{ARGV[0]}" but can you tell me why it's better to use puts than $stdout.print? I'm just curious. Again, thank you very much. PV Alex Gutteridge wrote: > On 22 Nov 2007, at 12:58, Peter Vanderhaden wrote: > >> $stdout.print "Invalid filename entered: argv[0] \n" > The literal answer to your question is: > > $stdout.print "Invalid filename entered: #{argv[0]}\n" > > But that's probably not what you really want. Firstly, You probably > mean ARGV instead of argv, so: > > $stdout.print "Invalid filename entered: #{ARGV[0]}\n" > > But that's (very, very nearly) the same as just: > > print "Invalid filename entered: #{ARGV[0]}\n" > > Which in Ruby is better written as: > > puts "Invalid filename entered: #{ARGV[0]}" > > This is the best place to get started IMHO: > > http://www.rubycentral.com/pickaxe/intro.html > > Alex Gutteridge > > Bioinformatics Center > Kyoto University -- Posted via http://www.ruby-forum.com/.