Meta programming: giving Integers a “fibonacci” property in Groovy

Image via Wikipedia

So, you just decide that each Integer should have an automatic property of knowing it’s Fibonacci number, well now your wish is granted:
Integer.metaClass.getFibonacci {
     fib = delegate
     def fibno = 1
     while (fib) {
         fibno += fibno
     fib--
     }
     return fibno
}

     Integer x = 25
     println x.fibonacci


I admit this is probably not the most useful additional property one could add to an integer and, of course, it is a function of an integer and not a property, but that was not my point…

Related articles

• Something interesting about Fibonacci numbers (cartesianproduct.wordpress.com)
• Something more on Fibonacci numbers (cartesianproduct.wordpress.com)
• From Irrational to Rational (ubpdqnmathematica.wordpress.com)