From: "Jesús Gabriel y Galán" <jgabrielygalan@...>
Date: 2008-05-13T18:41:46+09:00
Subject: Re: Handling of arrays

On Tue, May 13, 2008 at 5:22 AM, Clement Ow
<clement.ow@asia.bnpparibas.com> wrote:
> Jesús Gabriel y Galán wrote:
>  > On Mon, May 12, 2008 at 11:00 AM, Clement Ow
>  > <clement.ow@asia.bnpparibas.com> wrote:
>  >>
>
> >>   sd_a.each do |sd|
>  >>   $source, $destination, $selections, $file_exception = sd
>  >>      src = File.join $source, $selections
>  >>      puts src
>  >>      d= $d1
>  >>      dst= File.join $destination, d
>  >>      test = File.join $source, $file_exception
>  >
>  > Untested but change this:
>  >
>  >>      src1 = Dir.glob(src) - Dir.glob(test)
>  >
>  > to:
>  >
>  > src1 = $file_exception.inject(Dir.glob(src)) {|result, ex| result -
>  > Dir.glob(ex)}
>  >
>  > Also, doing a Dir.glob for each exception can be a lot, why not use
>  > regular expressions
>  > to remove from the result of the first glob? You will have to change
>  > the exceptions
>  > a little bit, but it might be worth it:
>  >
>  > ["\.txt", "\.sql"].inject(Dir.glob("/home/jesus/*")) {|result, ex|
>  > result.reject{|x| x =~ Regexp.new(ex)}}
>  >
>  > This removes from my home folder all files that match ".txt" and ".sql"
>  >
>  > Hope this helps,
>  >
>  > Jesus.
>
>  Hi Jesus,
>  nice slick code there using regexp ;) just wondering if there would be a
>  possibility of having a different set of file exceptions for different
>  file paths. cause at the moment, there can only be one specific file
>  exceptions for every file path, which might be hard in the event where
>  we would need to cater to different source paths. Prolly a few arrays in
>  file exception?

If what you want is to associate different information to each source path,
I would look into a hash of hashes or a hash of arrays, or a hash of structs,
where you could have a complex object for the info related to an entity of
your program. For example:

A hash of arrays, if you only need exceptions:

exceptions_by_path = {}
exceptions_by_path["/home/jesus"] = ["\.txt", "\.sql"]
exceptions_by_path["/home/jesus/applications"] = ["\.sh", "\.bin"]
# [...]

and then

paths.each do |path|
   files = exceptions_by_path.inject(Dir.glob("#{path}/*")) {|result,
ex| result.reject{|x| x =~ Regexp.new(ex)}}
end

If for a path you need several different things, I would go with a
Struct or a custom class:

FileInfo = Struct.new :exceptions, :other_value, :yet_another
paths_info = {}
paths_info["/home/jesus"] = FileInfo.new(["\.txt", "\.sql"], "other
value", "another")

and then access the exceptions array as paths_info["/home/jesus"].exceptions
and use it as before.

Hope this helps,

Jesus.