Robert Klemme
12/25/2006 5:21:00 PM
On 25.12.2006 18:08, Spitfire wrote:
> I've read that in Ruby the value returned from a code block is the
> value of the last expression executed. Is it so? If Yes, I don't
> understand the value returned by the following code block!
>
> def clistIter
> clist = [1, 2, 3]
> clist.each do |elem|
> yield(elem)
> end
> end
>
> clistIter { |e| print e }
>
> ## output in irb:
> ## 123 => [1, 2, 3]
> ##
> ## returned value:
> ## => [1, 2, 3]
>
> Can someone explain how come an array is returned as result?
Because #each ignores all return values from the block (it is invoked
once per element visited) and chooses to return self. This is how it
could look like internally (it's coded in C of course):
>> class Array
>> def demo_each
>> for i in 0...length
>> yield self[i]
>> end
>> self
>> end
>> end
=> nil
>> [1,2,3].demo_each {|e| p e; 666}
1
2
3
=> [1, 2, 3]
Kind regards
robert