Dynamically setting function type through xml

I have a number of functions and I want to execute 1 based on the entries in a .xml file

part my xml file reads as follows

<funcType>thisFunc</funcType>

In my .fla I have defined thisFunc along with a number of similar functions

I want to execute the function as follows

chosenFunc=Node.childNodes[0].childNodes[0].nodeValue;//points to thisFunc in the .xml file

chosenFunc(); // This should execute as thisFunc ()

Problem is this doesn’t seem to be working. Am I trying the impossible?