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Tookelso wrote:

> Hello,

Moin!

> When you pass an argument to a method, is it passed by reference, or by
> value?
> Or, does it depend on the object's type?
> 
> For example, in the simple script below, the program outputs "0".
> #-----------------------------------
> def test(c_count)
> c_count  _count + 1
> end
> # begin program
> c_count  
> test(c_count)
> puts c_count
> #-----------------------------------
> I realize that for simple things, it's better to return a value from
> the method, but I would like to know *why* it's not modifying my
> "c_count" value.

Arguments in Ruby are just objects that are passed via ref because it 
would not make much sense to get copies of your Objects all over the 
place. It's simpler to just request a copy of an Object if you need one. 
(Via Object#clone or #dup)

But note that variables are no Objects, they are just names for Objects!

So how do you accomplish the above? If you just want to return multiple 
values use something like this:

def wc(text)
   lines  ext.count "\n"
   words  ext.scan(/\S+/).size
   bytes  ext.size
   return [lines, words, bytes]
end

lines, words, bytes  c("hello world")

If you really want to do an assignment to a variable after the fact use 
something like this:

def inc_score(amount  , &block)
   block.call(amount)
end

score  
score_assign  ambda { |new_score| score  ew_score }
inc_score(5, &score_assign)

This uses blocks as a callback for doing the assignment.

If you really want boxed Variables (that can be handled as Objects) you 
can use the library I attached to do something like this:

def inc(var)
   var.value + 
end

x  
5.times { inc Variable[:x] }
Variable[:x].value # 6
x # 6


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