From: Ross Bamford <rossrt@...>
Date: 2006-04-12T22:24:15+09:00
Subject: Re: Simple substitutions

On Wed, 2006-04-12 at 22:04 +0900, Peter Bailey wrote:
>  Now, I'd like to 
> streamline my conversion and aim for the much smaller target file I 
> mentioned above. Right now, my target file is still 10mB big, with just 
> that one pages line replaced with what I want. So, instead of working in 
> line mode, do you think I should just read in the entire file and use 
> ".*" before and after my sub expression to get rid of everything else?
> 

Well, memory is cheap these days and I have to admit I'm much less
careful about how I use it (unless there's a specific reason to conserve
it) but in this case, if there's only one pages line in your file, then
how about doing something like (N.B. untested code):

	pages = nil
	File.foreach("test1.ps") do |line|
	  if line =~ /\%\%Pages: ([0-9]{1,5})/
	    pages = $1
	    break
	  end
	end

	if pages
	  File.open("psout.txt", "w") { |out| out << "Pages: #{pages}" }
	end

If you do choose to read the whole thing in at once, one way to achieve
that might be:

	pages = nil
	File.read('test1.ps').scan(/\%\%Pages: ([0-9]{1,5})/) do
	  pages = $1
	  break
	end

	if pages
	  File.open("psout.txt", "w") { |out| out << "Pages: #{pages}" }
	end

-- 
Ross Bamford - rosco@roscopeco.REMOVE.co.uk