17.1.6.1 Emulation of compile()
Keywords: lib

### 17.1.6.1 Emulation of `compile()`

While many useful operations may take place between parsing and bytecode generation, the simplest operation is to do nothing. For this purpose, using the `parser` module to produce an intermediate data structure is equivalent to the code

      >>> code = compile('a + 5', 'file.py', 'eval')
      >>> a = 5
      >>> eval(code)
      10

The equivalent operation using the `parser` module is somewhat longer, and allows the intermediate internal parse tree to be retained as an AST object:

      >>> import parser
      >>> ast = parser.expr('a + 5')
      >>> code = ast.compile('file.py')
      >>> a = 5
      >>> eval(code)
      10

An application which needs both AST and code objects can package this code into readily available functions:

      import parser

      def load_suite(source_string):
          ast = parser.suite(source_string)
          return ast, ast.compile()

      def load_expression(source_string):
          ast = parser.expr(source_string)
          return ast, ast.compile()