From: luisbebop <luisbebop@...>
Date: 2008-10-26T01:19:53+09:00
Subject: Re: Join all text files in a folder, with a single line of Ruby code

I got your point. We need an one loop, to be more efficient.
Really, I don't need deal with arbitrary large files.
Like as said, the main goals here are: use ruby (without prompt
commands), and one line of code.
Thanks :)

On Oct 25, 1:24 pm, Robert Klemme <shortcut...@googlemail.com> wrote:
> On 25.10.2008 15:47, William James wrote:
>
> > luisbebop wrote:
>
> >> I did a single line of code in Ruby, which joins all text files in a
> >> folder to a bigfile. I got some tests, and it's works!
> >> Does anyone knows a better way, or other 'Ruby Way' to do that ?
>
> >> File.open('bigfile','w') { |mergedFile| Dir.glob("*.txt").each { |
> >> file| File.readlines(file).each { |line| mergedFile << line } } }
>
> > "We don't need no stinkin' loops!"
>
> > ruby -e"puts ARGF.to_a" *.txt >merged
>
> There's also
>
> ruby -e '$defout.write(ARGF.read)' *.txt >merged
> ruby -e 'File.open("out","w") {|io| io.write(ARGF.read)}' *.txt
>
> > "We still don't need no stinkin' loops!"
>
> > File.open("mrg","w"){|f|f.puts Dir['*.txt'].map{|nm|IO.read nm}}
>
> That's vastly inefficient since it reads all the files into memory
> before writing a single byte.  This is not necessary.  You can at least
> improve to
>
> File.open("mrg","w"){|f|Dir['*.txt'].each{|nm|f.write(File.read(nm))}}
>
> But a proper solution (i.e. one that deals with arbitrary large files)
> would use a fixed buffer size - but that looks ugly on a single line...
>
> Kind regards
>
>         robert