From: Robert Klemme <shortcutter@...>
Date: 2010-08-18T20:27:06+09:00
Subject: Re: Making File.open work on gzipped files

2010/8/18 Martin Hansen <mail@maasha.dk>:
> Thanks Brian and Robert. The below snippet appears to be working nicely
> - though I am not sure that the file is closed if zipped?
>
>
>
> class Parser
>  def self.open(*args)
>    ios = File.open(*args)
>
>    begin
>      ios = Zlib::GzipReader.new(ios)
>    rescue
>      ios.rewind
>    end
>
>    parse = self.new(ios)
>
>    if block_given?
>      begin
>        yield parse
>      ensure
>        ios.close
>      end
>
>      return true
>    else
>      return parse
>    end
>  end
> end

I would apply these changes:

1. refactor opening code (everything before "if block_given?") into a
separate method which returns either IO or GzipReader.

2. fold parse and ios into one (i.e. the value returned from the other method).

See http://ruby-doc.org/core/classes/Zlib/GzipFile.html#method-M007448

3. In case of block_given? do not return true but rather nothing (i.e.
what the block returned).  This is more flexible.

That way your code will become simpler.

Kind regards

robert

-- 
remember.guy do |as, often| as.you_can - without end
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