dsp_099 dsp_099 - 2 months ago 8x
Ruby Question

How to read a large text file line-by-line and append this stream to a file line-by-line in Ruby?

Let's say I want to combine several massive files into one and then

the one (THAT alone might take a hot second)

It's my understanding that
loads ALL the lines into memory. Is there a way to read it line by line, sort of like how node.js
system works?


One of the great things about Ruby is that you can do file IO in a block:

File.open("test.txt", "r").each_line do |row|
  puts row
end               # file closed here

so things get cleaned up automatically. Maybe it doesn't matter on a little script but it's always nice to know you can get it for free.