Gary, sorry.
Have you meant something like this:
````java
public void afterPropertiesSet() throws Exception {
		ApplicationContext parent = this.applicationContext.getParent();
		SpelFunctionRegistrar parentFunctionRegistrar = parent.getBean(SpelFunctionRegistrar.class);
		Map<String, Method> parentFunctions = parentFunctionRegistrar.getFunctions();
		for (String key : parentFunctions.keySet()) {
			if(!this.functions.containsKey(key)) {
				this.functions.put(key, parentFunctions.get(key));
			}
		}
	}
````
?