From: Bill Kelly <billk@...>
Date: 2009-03-30T18:55:03+09:00
Subject: Re: Symbols garbage collector in Ruby1.9, fixed?


From: "I単aki Baz Castillo" <ibc@aliax.net>
> 2009/3/30 Bill Kelly <billk@cts.com>:
> >
> > From: "I単aki Baz Castillo" <ibc@aliax.net>
> >>
> >> 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
> >
> > potential_new_symbol = "xyzzy"
> > Symbol.all_symbols.map {|s| s.to_s}.include? potential_new_symbol
>
> Thanks but it is too slow:
>
> Benchmark.realtime{ Symbol.all_symbols.map {|s| s.to_s}.include? "qwe" }
> => 0.00371980667114258
>
> I cannot do this test for each header in each received message.

I assumed you had a plan for that.  :)

We could cache them as a hash, for rapid lookup:

  @known_symbols = Hash[ *Symbol.all_symbols.map {|s| [s.to_s,true]}.flatten ]

# Later....

  @known_symbols.include? "xyzzy"


Regards,

Bill