Here is my current method for editing files:
<code>
filename = File.join('path', 'to', 'file')
content =
File.open(filename, 'r') do |file|
content = file.readlines
end
content.collect! do |line|
line.gsub!(/six/, "half a dozen")
line.chomp
end
File.open(filename, 'w') do |file|
file.write content.join($/)
This is a killer because it will transform the whole file into a single String just for printing. You better do either of this
1. just do "file.puts content"
2. work with String the whole way, i.e.
content = File.read file_name
content.gsub! /six/, "half a dozen"
File.open(file_name, "w") {|io| io.write content}
First alternative has the advantage of being a smaller change to your code and also I believe it's nicer to the GC; second solution has the advantage that you can do multiline replacements.
end
</code>
This is expensive though, as it rewrites the entire file, even if only a
single word in the whole file is changed. I'm wondering if there is a
better way to do this.
For text files the situation is usually this: the replacement has different length than the original. Thus, you need to at least rewrite all the stuff from the original string's starting position on. The code becomes a bit more complex and if the file is small it's probably not worthwhile.
Note also that there is command line option -i which will allow for easy inline edits:
ruby -i.bak -pe 'gsub /six/, "half a dozen"' your_file
You can also use it in scripts:
#!/bin/ruby -i.bak -p
gsub /six/, "half a dozen"
Kind regards
robert
···
On 22.06.2008 06:16, James Dinkel wrote: