ast.py 文件源码

def execute(self, context):
        if self.cmd == sym.LIST:
            print('database relations:')
            for table in context.db.list():
                attrs = ['{}:{}'.format(attr, type.value)\
                         for attr, type in context.db.describe(table)]
                print('  {}({})'.format(table, ', '.join(attrs)))
            if len(context.views.list()) > 0:
                print('views defined:')
                for view in context.views.list():
                    raw_def = context.views.raw_def(view)
                    ast = RelExpr.from_view_def(raw_def)
                    logging.disable(logging.WARNING)
                    ast.validate(context)
                    logging.disable(logging.NOTSET)
                    print('  {}({}) {} {}'.format(view,
                                                  ', '.join(ast.type.str_attr_names_and_types()),
                                                  literal(sym.GETS), raw_def))
        elif self.cmd == sym.QUIT:
            sys.exit(0)