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copied!<pre><code>a=b=c=d=7 # a, b, c and d points to the same integer object "7" b = 8 # b now points to a new object "8" # "=" does not change the value of the pointer integer, # it assings a new reference like in the line above puts d # obviously, d still points to "7" c = 111 # c now points to another integer object "111" puts a # a still points to "7" d = 999 # d now points to a new integer object "999" puts b # b still points to "8" </code></pre> <p>in Ruby, the Integer object is immutable so you cannot assign an Integer to multiple reference and change its value after. </p> <p>As @pts suggested, you should use an array to wrap your Integer reference because Arrays are mutable to you are able to change the value after.</p> <pre><code>a=b=c=d=[7] b[0] = 8 puts d[0] c[0] = 111 puts a[0] d[0] = 999 puts b[0] </code></pre> <p>CLARIFICATION:</p> <p>If you come from a C++ background, it may be strange because C++ does 2 things with the same syntax, assigning the reference and changing the value referenced.</p> <pre><code>int a = 10; // creates an int on the stack with value 10 int& b = a; // creates a reference to an int and references the a variable b = 5; // change the value referenced by b (so a) to 5 // a and b now hold the value 5 </code></pre> <p>In Ruby, reference are mutable and integers are not (exactly the contrary to C++). So assigning a reference will actually change the reference and not the referenced value.</p> <p>Another solution would be to create a class that is a mutable integer:</p> <pre><code>class MutableInteger attr_writer :value def initialize(value) @value = value end def inspect value end def to_i value end def to_s value end end a = b = MutableInteger.new(10) a.value = 5 puts b # prints 5 </code></pre>

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