From: Dan George <endege@...>
Date: 2007-09-20T17:35:04+09:00
Subject: Re: YAML & readlines & modify text files

On Sep 20, 1:41 am, Stefano Crocco <stefano.cro...@alice.it> wrote:
> Alle gioved� 20 settembre 2007, Dan George ha scritto:
>
>
>
> > On Sep 20, 12:39 am, Stefano Crocco <stefano.cro...@alice.it> wrote:
> > > Alle mercoled� 19 settembre 2007, Dan George ha scritto:
> > > > CATEG being another line inside the text files... and the problem
> > > > might be because the Name-line isn't always above the Link-line. I
> > > > could have n lines between or below, what I'm trying to say is that I
> > > > don't know where the Name-line is inside the texts files.
>
> > > This changes everything. I assumed (according to the example lines you
> > > posted) that each Link-line had the corresponding Name-line above it.
> > > But, if there isn't a relation between the position of the two kind of
> > > lines, how can you know what to put in the link line? I mean, what is the
> > > relation which connects a Link-line and the corresponding Name-line?
> > > Since (from what you say now) the position of the two kind of lines are
> > > random (as far as this problem is concerned, at any rate) are you able,
> > > given a single Link-line, to understand which is the corresponding
> > > Name-line? If yes, how? Whithout knowing this, I can't help you.
>
> > > Stefano
>
> > All I can say is that in each text file there will only be one Name-
> > line and one Link-line. The only connection between this 2 lines is
> > that the Link uses the shorter version of what is written in the Name-
> > line (i.e. if the Name-line: New York the Link line will use NY)
>
> > Isn't it possible to read the Name-line, take the correspond value
> > from the YAML file, store it in a variable (string?) inside the code
> > and then use it in the Link-line, when going to the next text file
> > read again the Name-line and take the value from YAML and so on...
>
> If each file contains only one Name-line and one instance of the corresponding
> Link-line, this should work:
>
> require 'yaml'
>
> lnk='blabla.something.'
> op = '&=bla'
> hash = File.open('name.yaml'){|f| YAML.load f}
>
> Dir.glob('**/*.txt').each do |f|
>   lines = File.readlines f
>   name = nil
>   link_idx = nil
>   lines.each_with_index do |l, i|
>     if l.match(/Name-line:\s+(.*)$/) then name $1
>     elsif l.match(/Link-line/) then link = i
>     end
>     break if name and link_idx
>   end
>   if name
>     rep = hash[name]
>     if rep
>       lines[link_idx]="Link-line: #{lnk}#{rep}#{op}"
>       File.open(f, 'w'){|of| of.write lines}
>     else puts "name.yaml doesn't contain an entry for #{name} (file #{f})"
>     end
>   else puts "Couldn't find a Name line in file #{f}"
>   end
> end
>
> For each file, it loops each line looking for a Name-line or a Link-line. When
> it finds the former, it stores the name in the name variable; when it finds
> the latter, it stores its index in the link_idx variable. When both are
> found, the loop stops (no point in examining the remaining lines). If a name
> has been found and it corresponds to an entry in the hash, the line with
> index link_idx is replaced with a new one (I removed the call to gsub!, since
> we're rebuilding the entire line,  but you can put it back, if you need it),
> then the array is written to the file. If the Name-line wasn't found, or if
> the hash doesn't contain an entry for it, an error message is printed on
> screen and the next file is processed.
>
> I hope this helps
>
> Stefano

Thanks for your reply Stefano!

I had to do:
          link_idx = nil.to_i
otherwise I would get this error: `[]': no implicit conversion from
nil to integer (TypeError)

And it seems to be working but if I use this:
          lines[link_idx]="Link-line: #{lnk}#{rep}#{op}"
the Name-line is removed and is replaced by the "Link-line:
#{lnk}#{rep}#{op}" but the old Link-line = 0 is kept too.

If I use
         lines[link_idx].gsub!(/Link-line.*/, 'Link-line: '+lnk+rep
+op)
nothing happends, no errors, no modified files, no nothing.

I don't see anything wrong with the gsub! so what might be the problem?