scope.cc

/* File: scope.cc
 * --------------     
 * Each Scope object tracks its own hashtable and 
 * may have additional information about the particulars for this 
 * scope (class, fn, global, etc.)
 */

#include "scope.h"
#include "ast_decl.h"


Scope::Scope()
{
    table = new Hashtable<Decl*>;
}


/* Method: Lookup
 * --------------
 * Looks for an identifier in this scope only. Returns NULL if
 * not found.
 */
Decl *Scope::Lookup(Identifier *id)       
{
    return table->Lookup(id->GetName());
}


/* Method: Declare
 * ---------------
 * Adds an identifier to this scope and sets scope on declaration.
 * Prints error if declaration/definition conflicts with use of identifier
 * in this scope and returns false. If successful, returns true.
 */
bool Scope::Declare(Decl *decl)
{
  Decl *prev = table->Lookup(decl->GetName());
  PrintDebug("scope", "Line %d declaring %s (prev? %p)\n", decl->GetLocation()->first_line, decl->GetName(), prev);
  if (prev && decl->ConflictsWithPrevious(prev)) // throw away second, keep first
      return false;
  table->Enter(decl->GetName(), decl);
  return true;
}

void Scope::CopyFromScope(Scope *other, ClassDecl *addTo)
{
    Iterator<Decl*> iter = other->table->GetIterator();
    Decl *decl;
    while ((decl = iter.GetNextValue()) != NULL) {
        table->Enter(decl->GetName(), decl);
	  if (addTo) addTo->AddField(decl);
    }
}