I am just curious as to what are all the possible methods of iterating
through a code block in ruby.
The way I think of it is, you start with while/until and for, and while/until
can be used as a sort of 'do while' loop, too.
But normally, you wouldn't use these, you'd use something like
[1,2,3].each do |x|
# do something with x
end
Specifically, look up Enumerable, and blocks in general. I don't consider these
to be separate methods of iterating, since you could easily implement them
like this:
class Array
def each
if block_given?
for x in self
yield x
end
else
enum_for
end
end
end
So, the language is conceptually simpler -- there are at most five ways of
iterating, depending how you count (while, do-while, until, do-until, for).
But that's also not entirely honest, as things in the standard library are
often written in C for speed, even if they're _possible_ to write in Ruby.
Each is no exception.
So, to answer your question, there are very few ways that are built into the
language, though how many there are depends how you count. On the other hand,
there are an infinite number of ways you could define yourself. For example:
def twice
yield
yield
end
twice { puts 'hello' }