// Note: Identity based on globalID, so eq(new SymVar("a"), new SymVar("a")) is FALSE.
sclass SymVar > HasGlobalID {
  S name;
  
  *() {}
  *(S *name) {}
  
  public bool equals(O o) { ret o instanceof IHasGlobalID && eqHasGlobalID(this, (IHasGlobalID) o); }
  public int hashCode() { ret _hashCode(globalID); }
  
  toString { ret "SymVar" + (nempty(name) ? " " + name : "") + "[" + globalID() + "]"; }
}