codeop --- 编译Python代码

源代码： Lib/codeop.py

codeop 模块提供了可以模拟Python读取-执行-打印循环的实用程序，就像在 code 模块中一样。因此，您可能不希望直接使用该模块；如果你想在程序中包含这样一个循环，你可能需要使用 code 模块。

这个任务有两个部分:

  1. 能够判断一行输入是否完成了一个Python语句：简而言之，告诉我们是否要打印'">>>"'或'"..."'。

  2. Remembering which future statements the user has entered, so subsequent input can be compiled with these in effect.

The codeop module provides a way of doing each of these things, and a way of doing them both.

To do just the former:

codeop.compile_command(source, filename="<input>", symbol="single")

Tries to compile source, which should be a string of Python code and return a code object if source is valid Python code. In that case, the filename attribute of the code object will be filename, which defaults to '<input>'. Returns None if source is not valid Python code, but is a prefix of valid Python code.

If there is a problem with source, an exception will be raised. SyntaxError is raised if there is invalid Python syntax, and OverflowError or ValueError if there is an invalid literal.

The symbol argument determines whether source is compiled as a statement ('single', the default) or as an expression ('eval'). Any other value will cause ValueError to be raised.

注解

It is possible (but not likely) that the parser stops parsing with a successful outcome before reaching the end of the source; in this case, trailing symbols may be ignored instead of causing an error. For example, a backslash followed by two newlines may be followed by arbitrary garbage. This will be fixed once the API for the parser is better.

class codeop.Compile

Instances of this class have __call__() methods identical in signature to the built-in function compile(), but with the difference that if the instance compiles program text containing a __future__ statement, the instance 'remembers' and compiles all subsequent program texts with the statement in force.

class codeop.CommandCompiler

Instances of this class have __call__() methods identical in signature to compile_command(); the difference is that if the instance compiles program text containing a __future__ statement, the instance 'remembers' and compiles all subsequent program texts with the statement in force.