下面的巫术阅读你自己的危险（！）
我不知道你想用这个做什么，这是可能的，但这是一个可怕的黑客......
无论如何，我已经警告过你（！），如果这些东西在你最喜欢的语言中不起作用，那就幸运了......
from inspect import getargspec, ismethod
import inspect
def main():
@get_modified_values
def foo(a, f, b):
print a, f, b
a = 10
if a == 2:
return a
f = 'Hello World'
b = 1223
e = 1
c = 2
foo(e, 1000, b = c)
# intercept a function and retrieve the modifed values
def get_modified_values(target):
def wrapper(*args, **kwargs):
# get the applied args
kargs = getcallargs(target, *args, **kwargs)
# get the source code
src = inspect.getsource(target)
lines = src.split('\n')
# oh noes string patching of the function
unindent = len(lines[0]) - len(lines[0].lstrip())
indent = lines[0][:len(lines[0]) - len(lines[0].lstrip())]
lines[0] = ''
lines[1] = indent + 'def _temp(_args, ' + lines[1].split('(')[1]
setter = []
for k in kargs.keys():
setter.append('_args["%s"] = %s' % (k, k))
i = 0
while i < len(lines):
indent = lines[i][:len(lines[i]) - len(lines[i].lstrip())]
if lines[i].find('return ') != -1 or lines[i].find('return\n') != -1:
for e in setter:
lines.insert(i, indent + e)
i += len(setter)
elif i == len(lines) - 2:
for e in setter:
lines.insert(i + 1, indent + e)
break
i += 1
for i in range(0, len(lines)):
lines[i] = lines[i][unindent:]
data = '\n'.join(lines) + "\n"
# setup variables
frame = inspect.currentframe()
loc = inspect.getouterframes(frame)[1][0].f_locals
glob = inspect.getouterframes(frame)[1][0].f_globals
loc['_temp'] = None
# compile patched function and call it
func = compile(data, '<witchstuff>', 'exec')
eval(func, glob, loc)
loc['_temp'](kargs, *args, **kwargs)
# there you go....
print kargs
# >> {'a': 10, 'b': 1223, 'f': 'Hello World'}
return wrapper
# from python 2.7 inspect module
def getcallargs(func, *positional, **named):
"""Get the mapping of arguments to values.
A dict is returned, with keys the function argument names (including the
names of the * and ** arguments, if any), and values the respective bound
values from 'positional' and 'named'."""
args, varargs, varkw, defaults = getargspec(func)
f_name = func.__name__
arg2value = {}
# The following closures are basically because of tuple parameter unpacking.
assigned_tuple_params = []
def assign(arg, value):
if isinstance(arg, str):
arg2value[arg] = value
else:
assigned_tuple_params.append(arg)
value = iter(value)
for i, subarg in enumerate(arg):
try:
subvalue = next(value)
except StopIteration:
raise ValueError('need more than %d %s to unpack' %
(i, 'values' if i > 1 else 'value'))
assign(subarg,subvalue)
try:
next(value)
except StopIteration:
pass
else:
raise ValueError('too many values to unpack')
def is_assigned(arg):
if isinstance(arg,str):
return arg in arg2value
return arg in assigned_tuple_params
if ismethod(func) and func.im_self is not None:
# implicit 'self' (or 'cls' for classmethods) argument
positional = (func.im_self,) + positional
num_pos = len(positional)
num_total = num_pos + len(named)
num_args = len(args)
num_defaults = len(defaults) if defaults else 0
for arg, value in zip(args, positional):
assign(arg, value)
if varargs:
if num_pos > num_args:
assign(varargs, positional[-(num_pos-num_args):])
else:
assign(varargs, ())
elif 0 < num_args < num_pos:
raise TypeError('%s() takes %s %d %s (%d given)' % (
f_name, 'at most' if defaults else 'exactly', num_args,
'arguments' if num_args > 1 else 'argument', num_total))
elif num_args == 0 and num_total:
raise TypeError('%s() takes no arguments (%d given)' %
(f_name, num_total))
for arg in args:
if isinstance(arg, str) and arg in named:
if is_assigned(arg):
raise TypeError("%s() got multiple values for keyword "
"argument '%s'" % (f_name, arg))
else:
assign(arg, named.pop(arg))
if defaults: # fill in any missing values with the defaults
for arg, value in zip(args[-num_defaults:], defaults):
if not is_assigned(arg):
assign(arg, value)
if varkw:
assign(varkw, named)
elif named:
unexpected = next(iter(named))
if isinstance(unexpected, unicode):
unexpected = unexpected.encode(sys.getdefaultencoding(), 'replace')
raise TypeError("%s() got an unexpected keyword argument '%s'" %
(f_name, unexpected))
unassigned = num_args - len([arg for arg in args if is_assigned(arg)])
if unassigned:
num_required = num_args - num_defaults
raise TypeError('%s() takes %s %d %s (%d given)' % (
f_name, 'at least' if defaults else 'exactly', num_required,
'arguments' if num_required > 1 else 'argument', num_total))
return arg2value
main()
输出：
1 1000 2
{'a': 10, 'b': 1223, 'f': 'Hello World'}
你去吧...我不负责任何被恶魔吃掉的小孩或类似的东西（或者如果它破坏了复杂的功能）。
PS：inspect 模块是纯粹的EVIL。