Ruby read/write to file in 1 line of code

ruby code-golf
Calin picture Calin · Sep 18, 2011 · Viewed 16.5k times · Source

I am kind of a newbie to Ruby, I am working out some katas and I stuck on this silly problem. I need to copy the content of 1 file to a new file in 1 line of code

First try:

File.open(out, 'w').write(File.open(in).read)

Nice, but it's wrong I need to close the files:

File.open(out, 'w') { |outf| outf.write(File.open(in).read) }

And then of course close the read:

File.open(out, 'w') { |outf| File.open(in) { |inf| outf.write(outf.read)) } }

This is what I come up with, but it does not look like 1 line of code to me :(

Ideas?

Regards,

Answer

Andrew Grimm picture Andrew Grimm · Sep 19, 2011

Ruby 1.9.3 and later has a

File.write(name, string, [offset], open_args)

command that allows you to write a file directly. name is the name of the file, string is what you want to write, and the other arguments are above my head.

Some links for it: https://github.com/ruby/ruby/blob/ruby_1_9_3/NEWS , http://bugs.ruby-lang.org/issues/1081 (scroll to the bottom).

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