A script that allows you to merge 2+ functions into 1, using a cool workaround

InheritFunction.gml

//#macro super merge_functions // uncomment this if you prefer the name 'super'

///@function	merge_functions(func1, func2, <func3>)
///@param		{function} func1
///@param		{function} *func2
///@param		{function} *func3
function merge_functions() {
	var funcs = array_create(argument_count, undefined)
	
	for(var i = 0; i < argument_count; i++)
		funcs[i] = argument[i]
	
	var foo = new MergedFunction()
	foo.functions = funcs
	
	return foo.call
}

///@function	MergedFunction(func1, func2, <func3>)
///@param		{function} func1
///@param		{function} *func2
///@param		{function} *func3
function MergedFunction() constructor {
	self.functions = array_create(argument_count, undefined)
	
	for(var i = 0; i < argument_count; i++)
		self.functions[i] = argument[i]
	
	call = function() {
		var args = array_create(7, undefined)
		for(var i = 0; i < argument_count; i++) { args[i] = argument[i] }
		
		for(var i = 0; i < array_length(self.functions); ++i) {
			var func = self.functions[i]
			func(args[0], args[1], args[2], args[3], args[4], args[5], args[6]) // edit this if you need 
											    // more than 7 arguments in a function
		}
	}
}