A few months back, while porting some code from php to ruby, being a newbie that I am, I came across an issue.
The php code had a function as such:

public string functionName($var1, &$var2, $var3){}

Here the caller of the function gets to decide the name of the variable ($var2).
So, the caller can access the result from a variable name of the callers choice.

functionName("variablevalue", "variableName", "variableValue");
echo $variableName;

The code was procedural and had nothing to do with classes, methods or objects.

In ruby I had to provide a similar option where the caller can name the variable.
Here is how I had implemented this.

attr_accessor :userVar, :varName

Adding a couple of properties to the class. attr_accessor defines the get set methods.

def method_missing(meth, *x)
		if "#{meth}" == self.varName
	    	class << self
		    	self
		    end.send :define_method, meth do |args|
		    	 self.userVar
		    end
		    self.send "#{meth}", x
		else
			puts "#{meth} : Such a method does not exist!"
		end
end

This checks to see if the called method exists. Uses define_method .

def methodName(var1, userVar="", var3)
		// function
		self.userVar = userVar
		self.varName = "#{self.userVar}"
		self.userVar = self.result
		return self.return
end

 objectName.methodName(var1, "myvariable", var3)
 puts objectName.myVariable

The user input variable name is a new method/property which contains the result.