From: Overnight <NOSPAM_jazz_x@..._NOSPAM>
Date: 2002-09-05T07:45:35+09:00
Subject: Newbie Qs: startup time, Module.constants, chdir, Ruby distro's library

Hello there!

I'm new to Ruby and my first impressions are really good: after some 
experience with both Perl and Python, the clean OO-ness of Ruby has been 
exciting, not to talk about its "no surprises" approach.

My first questions are of various kind, please apologize me for mixing 
them in a single message:

1) on my *monster* PC (a glorious 200mhz Pentium box with W98...), Ruby's 
startup time is about 1 second (e.g., ruby -e "p 'hello world'" takes 1 
second) Isn't it too much? 
Using IRB is even worse: it takes about 2/3 seconds to show the first 
prompt, and about 0.5 seconds to process every line. Is this normal? Is 
it time for me to think to a Pentium II? :-)
I'm using Ruby 1.6.7, installed from ruby-1.6.7-i586-mswin32.zip (sorry, 
I don't remember the exact version of the executable I downloaded, but 
it's the one which does not require Cygwin or other support environments)

2) after browsing the Pragmatic Programmer's Guide, I did some tests with 
Module.constants and Module#constants. Now I really don't understand the 
following:

> module M
> 	Konst1=1
> end
>
> M.constants

['Konst1']

> class C
> 	Konst2=1
> end
>
> C.constants

["Konst2", "DATA", "FALSE", "ARGV", ...]

Why the different behaviour? I mean, why #constants returns just a 
module's own constans, and a class' own *and* inherited constants?

There is also the fact that:

> M::DATA

#<File:0x257cc5c>

> C::DATA

#<File:0x257cc5c>

Since DATA is accessible through M (as well as all other consts), 
shouldn't M.constants include it (together with all other consts)?

I've read about the C.constants-C.superclass.constants trick, my problem 
is not finding a way to discover C's own constants, I just would like to 
understand #constants has a different behaviour when it is applied to a 
module or a class.

2bis) To understand when Module.constants and Module#constants are 
called, I used:

class Module
	alias oldc constants
	def constants
		puts "constants"
		oldc
	end
	class <<self
		alias oldmc constants
		def constants
			puts "Module.constants"
			oldmc
		end
	end
end

Is this right? is is the right way to do it?

3) If I want to use a script to persistently (i.e., after Ruby's 
exit) change the working dir, how do I do? Neither

ruby -e "system('cd \\'); puts Dir.getwd"

nor 

ruby -e "Dir.chdir('\\'); puts Dir.getwd"

seem to work

4) Comparing Ruby with the Pythonesque "batteries included" approach 
wasn't very exciting... At times I think that Python (ActiveState) distro 
is overloaded, but all in all I prefer too many (optional) features than 
too few. Is there a reference Ruby library? Are there distros supporting 
it?

That's all for now. My compliments to Matz, I really like the language, 
its simplicity and its object orientation, definitely one step above the 
competition.

And thank you in advance for your help.

Andrea (which, FYI, is a *male* name here in Italy :-) )