zip lines of two files

file_zip.rb

# under CC0 License

# zips the lines of two files
# don't know how to extend ruby
# instead made a function
# this works cuz `File.open(file, "r").each` return an Enumerable of lines

$i = { a: "#{__dir__}/a.txt", b: "#{__dir__}/b.txt" }
$o = "#{__dir__}/o.txt"

def file_zip(a, b)
	return File.open(a, "r").each.zip(File.open(b, "r").each)
end

o = file_zip($i[:a], $i[:b]).map { |zipped_lines| zipped_lines.join }

File.open($o, "w") { |file| file.write(o.join) }

IO.write('c.txt', IO.foreach('a.txt').zip(IO.foreach('b.txt')).join)

@gr33n7007h don't you need to close an IO after opening it like that?

Both IO.write and IO.foreach ensure that the underlying io is closed.