From: Rob Biedenharn <Rob@...>
Date: 2008-02-14T08:22:21+09:00
Subject: Re: my noob "numbering lines" programe. How to improve?

On Feb 13, 2008, at 5:50 PM, Adam Akhtar wrote:

> Give us hints on how to improve this program. If you want to show your
> code off then go ahead but please give us the hints first i.e. what
> methods you would use, what you would rewrite in my code etc. Its so
> much better for me to go away and try and replicate your thinking than
> just reading it.
>
> heres my version
>
> #program to insert numbers infront of lines.
> def numbertext(infilename, outfilename)
>  #for neat formating work out how many lines there are first so we  
> know
> how       #many digits to set ljust to
>  totalnumlines = File.readlines(infilename).length
>  numdigits = 1
>  x = 1
>  while (x < totalnumlines)
>    x = x * 10
>    numdigits = numdigits + 1
>  end

Since the representation of numbers doesn't shrink and you already  
have totalnumlines (which would typically be total_num_lines), perhaps  
you could think of a direct way of finding the number of character  
positions that you'd need to reserve for this largest number.

>
>  linenumber = 0
>  File.open(outfilename, "w") do |output|
>    File.foreach(infilename) do |input|
Too bad you didn't save the lines when you read the file the first  
time... then you could have used .each_with_index.  You could even use  
$. to get the current line number from the file rather than keep your  
own explicit counter in linenumber.  (Which would be idiomatically  
line_number += 1)

>
>      output.write linenumber.to_s.rjust(numdigits) + " " + input
>      linenumber = linenumber + 1
>    end
>  end
> end
> -- 


All hints, no code. ;-)

-Rob

Rob Biedenharn		http://agileconsultingllc.com
Rob@AgileConsultingLLC.com