From: "Iñaki Baz Castillo" <ibc@...>
Date: 2009-03-30T18:17:40+09:00
Subject: Re: Symbols garbage collector in Ruby1.9, fixed?

2009/3/30 F. Senault <fred@lacave.net>:
>
> It depends on what exactly you are trying to do with your hash.  If you
> need to access to a few well known headers in your code, use symbols for
> those and add another pseudo-header for the rest of the info :
>
> USEFUL_HEADERS = [ :from, :to, :"x-mailer" ]
>
> headers = {
>  :from => "alice@aaa.com",
>  :to => "bob@bbb.com",
>  :"x-mailer" => "Pegasus Mail for Windows (4.50 PB1)",
>  :"_custom" => {
>    "x-custom-header-1" => "Hi there",
>    "x-spam-scanned" => "Of course"
>  }
> }
>
> (Now, you'll lose time at the parse step.  Again, depending on what
> you're trying to do, it may be efficient if each mail is parsed one time
> and, then, each header is accessed a lot of times.)

Thanks, but I prefer to store all the headers in a transparent way so
accessing to a core and well known header is the same as accesing to a
custom and never seen header:
  headers[:from]
  header[:"x-custom-headers"]

This is, in the transport/parsing layer I cannot know which headers
will be important or not in the "application" layer.

A way to check if a Symbol already exist would be enought for me, but
it doesn't work:
To know all the current Symbols I can inspect Symbol.all_symbols, but
if I want to check a Symbol:
  Symbol.all_symbols.include?(:new_symbol)
this will always return true since :new_symbol is automatically added  XDDD

Thanks.

-- 
Iñaki Baz Castillo
<ibc@aliax.net>