December 2014
Beginner
336 pages
7h 41m
English
book
Learn Ruby the Hard Way: A Simple and Idiomatic Introduction to the Imaginative World of Computational Thinking with Code, Third Edition
by Zed A. Shaw
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Exercise 17. More Files
Now let’s do a few more things with files. We’ll write a Ruby script to copy one file to another. It’ll be very short, but will give you ideas about other things you can do with files.
ex17.rb
1 from_file, to_file = ARGV 2 3 puts "Copying from #{from_file} to #{to_file}" 4 5 # we could do these two on one line, how? 6 in_file = open(from_file) 7 indata = in_file.read 8 9 puts "The input file is #{indata.length} bytes long" 10 11 puts "Does the output file exist? #{File.exist?(to_file)}" 12 puts "Ready, hit RETURN to continue, CTRL-C to abort." 13 $stdin.gets 14 15 out_file = open(to_file, 'w') 16 out_file.write(indata) 17 18 puts "Alright, all ...
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I'm always learning. So when I got on to O'Reilly, I was like a kid in a candy store. There are playlists. There are answers. There's on-demand training. It's worth its weight in gold, in terms of what it allows me to do.