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From: Eva on 23 Dec 2009 21:36
Hi,

Please take a look at below:

def mytest
return [1..10]
end

x = mytest
x.each do |c| puts c end


this works not as I expected.
I want the output of:
1
2
3
4
5
6
7
8
9
10


But if I change return [1..10] to return 1..10 it will work.
So what's the difference between 1..10 and [1..10]?
THanks.


From: Steve Klabnik on 23 Dec 2009 21:47
[Note: parts of this message were removed to make it a legal post.]

1..10 is a range, while [1..10] is an array with one element, a range from
1..10. You can think of 1..10 as (1..10) and [1..10] as [(1..10)]

I am 95% sure that this is correct, someone please correct me if I'm wrong.
irb seems to support this:

> def one_to_ten
> 1..10
> end
=> nil
> one_to_ten.class
=> Range
> [1..10].class
=> Array

From: Eva on 23 Dec 2009 22:29
On Thu, 2009-12-24 at 11:47 +0900, Steve Klabnik wrote:
> 1..10 is a range, while [1..10] is an array with one element, a range from
> 1..10. You can think of 1..10 as (1..10) and [1..10] as [(1..10)]
>
> I am 95% sure that this is correct, someone please correct me if I'm wrong.
> irb seems to support this:
>
> > def one_to_ten
> > 1..10
> > end
> => nil
> > one_to_ten.class
> => Range
> > [1..10].class
> => Array


Thanks for the reply. I'm newbie to Ruby,so have another question, I
want to make a function who returns the result which can be used as:

mytest do |a,b|c| do_something end

How to write this mytest?

Regards,
Eva


From: Justin Collins on 24 Dec 2009 00:48
Eva wrote:
> On Thu, 2009-12-24 at 11:47 +0900, Steve Klabnik wrote:
>
>> 1..10 is a range, while [1..10] is an array with one element, a range from
>> 1..10. You can think of 1..10 as (1..10) and [1..10] as [(1..10)]
>>
>> I am 95% sure that this is correct, someone please correct me if I'm wrong.
>> irb seems to support this:
>>
>> > def one_to_ten
>>
>>> 1..10
>>> end
>>>
>> => nil
>>
>>> one_to_ten.class
>>>
>> => Range
>>
>>> [1..10].class
>>>
>> => Array
>>
>
>
> Thanks for the reply. I'm newbie to Ruby,so have another question, I
> want to make a function who returns the result which can be used as:
>
> mytest do |a,b|c| do_something end
>
> How to write this mytest?
>
> Regards,
> Eva
>
>

The do...end is actually creating a block, which is passed into your
method. There are two ways of having functions accept blocks:

#Explicitly
def mytest &block
block.call 1, 2, 3
end

#Implicitly
def mytest
yield 1, 2, 3
end

Either way can be called like

mytest do |a,b,c|
do_something_with a, b, c
end

You will probably want to read up on methods and blocks and how the two
can be used together.

-Justin

From: Eva on 24 Dec 2009 00:54
Thanks all!
Merry Christmas Ruby world.

--
Kind Regards,
Eva.


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