Re: increasing counter whithin loop?

Quoting Patrick Gundlach <clr9.10.randomuser@xxxxxxxxxxxxxxx>:

> sequence.each do |element|
> ....
> end
>
> would be nice, but I understand that there is no
> 'skip_the_next_element'-method. So the next nicer attempt would
> be
>
> for counter in 0...element.size
> # ...
> increase_counter_by_one_to_skip_one_interation
> end
>
> But - contradicting my intuition - doesn't seem to work/exist. So
> I have to stick to an ugly while loop.... ;-) So my question is:
> did I miss something?

There's really no difference between:

for counter in 0...element_size
...
end

and

(0...element_size).each do |counter|
...
end

Both call Range#each with the given block.

> Is there any reason why we can't manipulate the counter within
> the loop?

'counter' isn't actually a counter. It's just a parameter of the
block given to Range#each. While there's probably a real counter
behind the scenes somewhere, it's not exposed to you.

90% of the time you don't need counters or while loops, though.
Even here, there's nothing preventing you from doing e.g.:

skip = false
sequence.each do |element|
if skip
skip = false
next
end
...
# set skip to true to skip the next iteration
...
end

or alternately:

skip = false
sequence.each do |element|
unless skip
...
# set skip to true to skip the next iteration
...
end
skip = false
end

-mental


.

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