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Another Ruby Except Method

In a previous article I documented an "except" method for arrays in Ruby.  This method returns a copy of the array excluding elements which equal objects passed in the argument.  An example of how it's used:

newArray = myArray.except(foo, bar)

newArray will contain all of myArray's elements except those which equal foo and bar.

In many cases, the program may only need to execute a function on each of the array's members, so creating a new array is overkill.  One solution is an each_except method:

myArray.each_except(foo, bar) { |child|
    puts "This element: #{child}"
}

The above code will execute the procedure for each element in the array that is not equal to foo or bar.

Following is the code to extend the Array class with except, except!, and each_except methods:

class Array
    def except(*exceptions)
        result = self.clone
        result.delete_if { |i|
            exceptions.include?(i)
        }
        result
    end
    def except!(*exceptions)
        self.delete_if { |i|
            exceptions.include?(i)
        }
        self
    end
    def each_except(*exceptions)
        self.each { |i|
            if exceptions.include?(i) == false
                yield(i)
            end
        }
    end
end

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