From: Peter Hickman <peter@...>
Date: 2001-11-30T21:24:26+09:00
Subject: [ruby-talk:27054] Using Enumerable

Im trying to write my own each method for a 'sort of' range class that
gets its data from
a file (but will have to process it before passing it on). The following
bit of code fails!

Just how do you write an each method?

#!/usr/local/bin/ruby

def testing(f)
        print " First...\n"
        f.each {|n| print "  #{n}\n" }

        print " Second...\n"
        f.each {|n|
                print "  #{n}\n"
                if n == 5 then
                        break
                end
        }
end

class Fred
        include Enumerable

        def initialize
                @end = 10
                @pointer = 0
        end

        def each
                if @pointer == @end then
                        return nil
                else
                        @pointer += 1
                        return @pointer
                end
        end
end

print "Using a range...\n"
f = (1..10)
testing(f)

print "Our new class...\n"
f = Fred.new
testing(f)