Enforce two illegal import statements that were outlawed in the reference manual but not checked: Names bound by import statemants may not occur in global statements in the same scope. The from ... import * form may only occur in a module scope. I guess these changes could break code, but the reference manual warned about them. Several other small changes If a variable is declared global in the nearest enclosing scope of a free variable, then treat it is a global in the nested scope too. Get rid of com_mangle and symtable_mangle functions and call mangle directly. If errors occur during symtable table creation, return -1 from symtable_build(). Do not increment st_errors in assignment to lambda, because exception is not set. Add extra argument to symtable_assign(); the argument, flag, is ORed with DEF_LOCAL for each symtable_add_def() call.