/** Add a symbol to our scope */
void add(Definition def) {
// Check to see if we already have a definition
Definition oldDef = (Definition) elements.get(def.getName());
// If so, we'll create a MultiDef to hold them
if (oldDef != null) {
// If the symbol there so far was not a MultiDef
if (!(oldDef instanceof MultiDef)) {
// remove the old definition
elements.remove(oldDef);
// create a new MultiDef
MultiDef newMulti = new MultiDef(def.getName(), oldDef);
// add the old symbol to the MultiDef
newMulti.addDef(oldDef);
oldDef = newMulti;
// add the MultiDef back into the scope
elements.put(def.getName(), oldDef);
}
// We now have a multidef, so add the new symbol to it
((MultiDef) oldDef).addDef(def);
}
// Otherwise, just add the new symbol to the scope
else {
elements.put(def.getName(), def);
def.setParentScope(this);
}
}
/**
* Lookup a method in the scope This is usually just a hashtable lookup, but if the element
* returned is a MultiDef, we need to ask it to find the best match
*/
Definition lookup(String name, int numParams) {
// Try to find the name in our scope
Definition d = (Definition) elements.get(name);
// if we found multiple defs of the same name, ask the multidef
// to do the resolution for us.
if (d instanceof MultiDef) return d.lookup(name, numParams);
// if we got a method back, check to see that the params apply
else if (d instanceof MethodDef)
if (((MethodDef) d).getParamCount() == numParams) return d;
else return null;
else return d;
}