From: Robert Klemme <shortcutter@...>
Date: 2007-01-12T23:15:10+09:00
Subject: Re: Splitting a multirecord per file format to a single record per file format: Right approach?

On 12.01.2007 15:02, Randy Kramer wrote:
> I'm trying to write essentially what I guess you'd call a filter (or maybe not 
> quite exactly).  It needs to:
> 
>    * read multi-line records from a file (one record at a time)
>    * then, with that one record:
>       * prepend some additional lines
>       * make substitutions for some of the lines already in the record
>       * grab some other portions of the record (less than a line, but usually 
> multiple words), find the "non-null" pieces, and incorporate those in  
> another header line
>       * create a unique filename
>       * write that (single) record to that file
[...]
> 3. The content of the files I have to convert is actually more like this:
> 
> <bof>
> Record header ('\x80\x81\x82\x83')
> 
> Record (with blank lines)
> (trailing blank line)
> Record header ('\x80\x81\x82\x83')
> 
> Record (with blank lines)
> (trailing blank line)
> Record header ('\x80\x81\x82\x83')
> 
> Record (with blank lines)
> <eof>

You could do:

# create a class for your records or use OpenStruct
YourRecord = Struct.new :name, :length, :foo, :bar
   def dump()
     File.open(file_name, "w") do |io|
       # whatever
     end
   end
end


current = nil

File.foreach('your file') do |line|
   line.chomp!

   case line
     when /^<bof>$/
       current = YourRecord.new
     when /^<eof>$/
       current.dump
       current = nil
     when /Record header/
     ...
     else
       # ignore or whatever
   end
end

Kind regards

	robert