无法从评估的 lambda 函数中获取源代码

Question

我遇到了这个有趣的事实，我想知道如何克服它。通过使用 inspect 很容易获得 lambda 的源代码。但是，一旦您 return 来自 eval 语句的完全相同的 lambda，获取源函数就会失败。

import inspect

f = lambda a: a*2
f2 = eval("lambda a: a*2")

inspect.getsource(f), inspect.getsource(f2)


/usr/lib/python3.7/inspect.py in getsource(object)
    971     or code object.  The source code is returned as a single string.  An
    972     OSError is raised if the source code cannot be retrieved."""
--> 973     lines, lnum = getsourcelines(object)
    974     return ''.join(lines)
    975 

/usr/lib/python3.7/inspect.py in getsourcelines(object)
    953     raised if the source code cannot be retrieved."""
    954     object = unwrap(object)
--> 955     lines, lnum = findsource(object)
    956 
    957     if istraceback(object):

/usr/lib/python3.7/inspect.py in findsource(object)
    784         lines = linecache.getlines(file)
    785     if not lines:
--> 786         raise OSError('could not get source code')
    787 
    788     if ismodule(object):

OSError: could not get source code

有没有办法解决这个问题并获取评估代码的源代码？

Answer 1

Functions don't remember their source code - all they know is the filename and line numbers they came from. If the function definition wasn't in a physical file that is still available, then it is utterly impossible for inspect.getsource() to work. You'd need a decompiler, instead.

谢谢，杰森哈珀

无法从评估的 lambda 函数中获取源代码

Can't get source code from an evaluated lambda function

python

eval

inspect