From: Mark Woodward <markonlinux@...>
Date: 2007-01-07T19:31:57+09:00
Subject: Re: Array questions

On Thu, 04 Jan 2007 11:56:09 +0100, Robert Klemme wrote:

> On 03.01.2007 23:58, Mark Woodward wrote:
>> I suspected that but I couldn't understand how/why this could be done
>> with a size 0.
>> 
>> @paths = Array.new(0,Array.new(0)) to me reads as "create a new array
>> with nothing in it and make that nothing reference another empty
>> array?"
>> ie []
> 
> Nothing cannot really reference to anything, can it?

Not that I'm aware of ;-).

> 
>> @paths = Array.new(1,Array.new(0)) This, if my logic's right, reads as
>> "create a new array with a single element that's an empty array.
>> ie [[] ]
> 
> Even that could be more clearly done with
> 
> @paths = [[]]
> 
>> Are you saying that even though @paths is created as an empty array, it
>> expects the first element it gets to be an array? If not it will throw
>> an error?
>> Sorry, I can't check this in irb ATM. 
> 
> No, there is no such error checking done.  There is also not a default 
> value as with a Hash - an Array always returns nil when non existing 
> elements are referenced.
> 
> Maybe the code was created and then modified several times leaving this 
> artifact.  The shortest and also cleanest solution would probably be to 
> just do
> 
> @paths = []

Thanks Robert, I checked this in irb when I got the chance and you're
right. There's no error checking. I can put what ever I like in 
    @paths = Array.new(0,Array.new(0))

just as I can 
    @paths = []

so I'll chalk it up as a artifact as you suggested above.

> 
> Kind regards
> 
> 	robert



cheers,


-- 
Mark