A class showing each variable scope in use

this example from a Well House Consultants training course
More on this [link]

This example is described in the following article(s):
• Scope of variables - important to Ruby on Rails - [link]

This example references the following resources:
http://www.google.com/url?sa=t&source=web&ct=res&cd=1&ved=
http://www.wellho.net/resources/ex.php4
http://www.wellho.net/resources/ex.php4

Source code: hit.rb Module: R102

$noah = 2

class Hit

        @@owmany = 0

        def initialize(sourcedata)
        stuff = sourcedata.split(/\s+/)
        @retain = stuff[0]
        @asked = 0
        @@owmany += $noah
# stuff - no @ - local to method
# @asked - one @ - an object variable (local to the object)
# @@owmany - two @s - a class variable - just one for the whole class

# object variable -> dynamic variable
# class variable -> static variable

# $ is a global variable!

        end

        def is_it_html()
        @asked = 1
        return @retain
        end

        def asked()
        return @asked
        end

        def summer()
        vals = @retain.split(/\./)
        sum = 0
        vals.each do |byte|
                sum += byte.to_i
                end
        return sum
        end

        def counter()
        return @@owmany
        end

        def lessthan(other)
                xx1 = self.summer()
                xx2 = other.summer()
                if xx1 < xx2
                        return self
                end
                return other
        end

        def < (other)
                xx1 = self.summer()
                xx2 = other.summer()
                if xx1 < xx2
                        return nil
                end
                return 1
        end

end

# And code to test that class if we run as a standalone program

if __FILE__ == $0

record1 = '68.84.191.190 - - [27/Jan/2010:03:30:04 +0000] "GET
/resources/ex.php4?item=j714/Strtok.java HTTP/1.1" 200 17773
"http://www.google.com/url?sa=t&source=web&ct=res&cd=1&ved=
0CAgQFjAA&url=http%3A%2F%2Fwww.wellho.net%2Fresources%2Fex.php4
%3Fitem%3Dj714%2FStrtok.java&rct=j&q=stringtokenizer+example&ei=
drRfS-6wGJDQM6XYlOwL&usg=AFQjCNENV_SaKA92HeAd5Tjr5PomobG7-A"
"Mozilla/5.0 (Windows; U; Windows NT 6.1; en-US; rv:1.9.1.7)
Gecko/20091221 Firefox/3.5.7 (.NET CLR 3.5.30729)"'

record2 = '68.84.191.191 - - [27/Jan/2010:03:30:05 +0000]
"GET /bing/C3.css HTTP/1.1" 200 6635 "http://www.wellho.net/resources/ex.php4
?item=j714/Strtok.java" "Mozilla/5.0 (Windows; U; Windows NT
6.1; en-US; rv:1.9.1.7) Gecko/20091221 Firefox/3.5.7 (.NET CLR 3.5.30729)"'

v1 = Hit.new(record1)
v2 = Hit.new(record2)
v3 = Hit.new('68.84.191.196 - - [27/Jan/2010:03:30:05 +0000]
"GET /bing/C3.css HTTP/1.1" 200 6635 "http://www.wellho.net/resources/ex.php4
?item=j714/Strtok.java" "Mozilla/5.0 (Windows; U; Windows NT 6.1;
en-US; rv:1.9.1.7) Gecko/20091221 Firefox/3.5.7 (.NET CLR 3.5.30729)"')
v4 = v1

v1 = Hit.new("192.168.200.134 hub-a-dub-dub")

p v1,v2,v3,v4

henry = [v1,v2,v3,v4]

p v2.asked

henry.each do |ford|
        r1 = ford.is_it_html
        p ford,r1
        p ford.counter
        p ford.summer
end

p v2.asked

vless = v2.lessthan(v3)
print vless.is_it_html

if v2 < v3
        puts "dis"
else
        puts "dat"
end

end

#* Sample Output
#*
#* WomanWithCat:r102 grahamellis$ ruby hit.rb
#* #<Hit:0x007fa060a21810 @retain="192.168.200.134", @asked=0>
#* #<Hit:0x007fa060a22170 @retain="68.84.191.191", @asked=0>
#* #<Hit:0x007fa060a21cc0 @retain="68.84.191.196", @asked=0>
#* #<Hit:0x007fa060a22670 @retain="68.84.191.190", @asked=0>
#* 0
#* #<Hit:0x007fa060a21810 @retain="192.168.200.134", @asked=1>
#* "192.168.200.134"
#* 8
#* 694
#* #<Hit:0x007fa060a22170 @retain="68.84.191.191", @asked=1>
#* "68.84.191.191"
#* 8
#* 534
#* #<Hit:0x007fa060a21cc0 @retain="68.84.191.196", @asked=1>
#* "68.84.191.196"
#* 8
#* 539
#* #<Hit:0x007fa060a22670 @retain="68.84.191.190", @asked=1>
#* "68.84.191.190"
#* 8
#* 533
#* 1
#* 68.84.191.191dat
#* WomanWithCat:r102 grahamellis$

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