Using symbolicNames in rules is very different from using make macro names because symbolicNames are evaluated at checking time and not at loading time. This is important because in interactive mode VMake recognizes changes to the description files and automatically reloads them overriding old information. So a local change of a symbolicName is immediately globally available without user interaction. This implies, that symbolicNames are resolved each time VMake finds one in the dependence list of a goal. Since VMake uses a typed object oriented approach for identifying files, it can check that a symbolicName references the right file type, e.g., an object library is created from compiled source files.