From: mengx@...
Date: 2002-01-03T03:17:43+09:00
Subject: [ruby-talk:30063] Re: A Bug or something else?

> 
> m> What is opinion on the rationale of "nil" -> "" ?
> 
>  All objects in ruby can have a string representation.
> 

They do need to have to string representation when needed.
nil.inspect returns a reasonable  string representation,
and send "inspect/nil?" to nil is reasonable. But is it reasonable 
to send "to_s, to_i" to "nil"?. If o.nil? == true, special handling
would have to be done (such as exiting process, raise exception, 
do assignment, call some functions..)
so that "o" can become a meaningful object. e.g.

a = {1=>2, 3=>4}
"#{a[5]}" -> ""

I assume people have similar program errors once in a while,
(much like often stumbling on "a"[0] is not a char :-)
which silently corrupts data. After finding such errors, usually
some handling is done like the following:

if a[5].nil?
	a[5] = 6
end
"#{a[5]}" -> "6"

With all this in mind, would you agree that at least for "nil",
the built-in one should disable "to_s/to_i/to_a" as it does not seem to
help in anyway to make correct program.

Thanks

-Ted