From: Russell Me <russ@...>
Date: 2008-02-09T14:20:30+09:00
Subject: Re: info on block arguments

Day wrote:
> On Feb 8, 2008 10:22 PM, Russell Me <russ@geekwhiz.com> wrote:
>> So, after 3 days I still don't understand this. Is it really that
>> difficult, or am i just plain dumb?
> 
> It is not exactly a simple concept. Especially, I think, if you're not
> familiar with object oriented thinking.
> 
>> While I'm looking to understand the kitty_toys sort, it's really just
>> because I want to know how it all works.
> 
> I think, actually, that _why's example is pretty complex, so maybe it
> would be better for stick with your 3.times example.
> 
>> even this:
>> 3.times {|x| puts x }
>>
>> I see it work, I understand what's going on, but I don't know HOW it's
>> working.
> 
> Actually. Maybe let's make it simpler. Forget, for the moment, about
> the |x| bit. Let's look at this code:
> 
> 3.times { puts "Arr!" } # Very high seas.
> 
> The block, there, is sort of where you store code for a second. So you
> wrap up something to be executed (the puts statement in this case) in
> a block and you hand it to the times method. Not every method can
> accept a block like that, but this one can.
> 
> So what the times method does is it executes whatever's in the block
> it got handed a number of times equal to the integer it was called on
> (three in this case). It sort of says, in English:
> Do 'puts "Arr!"' three times.
> 
> If you're entirely new to OOP, it may be hard to remember or envision
> this, but: The code does not execute in sequence. Remember that 3 is
> an object. It is doing something (the method). It can do that thing,
> on stuff that you hand it (a block in this case, but this is true for
> all arguments). Really, the key difference between a block and any
> other argument you might pass to a method is that a block is code that
> can be executed, but the execution is held off until the method it's
> passed to asks it to execute.
> 
> Does that make some sense? If you get that alright, then I think it'll
> be a bit easier to move on to the more complicated examples. Kudos, by
> the way, for your perseverence. Lesser men would have given up in
> frustration by now. I hope you don't feel like you're being badgered
> or yelled at or ganged up on. Hang in there. You'll get it.
> 
> 
> Ben

Ben,

that actually was helpful. Understanding that the crap inside the block 
gets executed 3 times. that makes sense.

the kitty toys thing is simply what why threw at me (the reader). too 
complicated? perhaps. it's the block itself then i don't get. everything 
else i understand, for the most part.

I appreciate the help (and attempts at help) from everyone. this seems 
to be a very friendly group. This seems such a trivial simple thing, but 
i can't wrap my little brain around it.

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