From: walter@...
Date: 2004-01-19T09:40:20+09:00
Subject: Re: setting instance variable "dynamically"


> I saw in the pickaxe there's a way to call methods dynamically, with
> send("method_name"):
> 
> "test".send("length")  # 4
> 
> What I want to do is set a variable this way. Is it possible?
> 

Using the following

class Q
    attr_accessor :field
end
q = Q.new

here are some times for looping 1000000 times setting the index:
i.e. 1.upto(1000000){|i| <set method> }

q.send("field=", i) took 2.203 seconds
q.send(:field=, i) took 1.251 seconds
q.instance_eval{field = i} took 4.187 seconds
q.instance_variable_set  "@field", i took 2.032 seconds
q.instance_variable_set  :@field, i took 1.072 seconds
q.field = i took 0.921 seconds

P.S. These timings are for the PragProg installer
ruby 1.8.0 (2003-08-04) [i386-mswin32]


Walt
*****************************************************
Walter Szewelanczyk
IS Director
M.W. Sewall & CO.        email : walter@mwsewall.com     
259 Front St.            Phone : (207) 442-7994 x 128
Bath, ME 04530           Fax   : (207) 443-6284
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