在Python中评估动态生成的语句 [英] Evaluating dynamically generated statements in Python

问题描述

我需要动态生成python代码并使用eval()函数执行它.

I need to dynamically generate python code and execute it with eval() function.

我想做的是生成一些导入"和分配值".我的意思是，我需要生成此字符串以对其进行评估eval(x).

What I would like to do is to generate some "imports" and "assign values". I mean, I need to generate this string to evaluate it eval(x).

x = """
import testContextSummary
import util.testGroupUtils
testDb = [testContextSummary.TestContextSummary, 
          testGroupUtils.testGroupUtils.TestGroupUtils]
""" # x is automatically generated
eval(x)
... use testDb ...

我尝试使用此代码，但是eval()返回无法识别import的错误，因此我尝试了此代码.

I tried with this code, but eval() returns an error not recognizing import, so I tried this code.

x = """
testContextSummary = __import__("testContextSummary")
testGroupUtils = __import__("util.testGroupUtils")
testDb = [testContextSummary.TestContextSummary, 
          testGroupUtils.testGroupUtils.TestGroupUtils]
""" # x is automatically generated

eval(x) # error

我再次遇到错误，不允许执行赋值语句.

I again got an error not allowing assignment statement.

有什么方法可以执行动态生成的python脚本，并使用评估结果?

Is there any way to execute dynamically generated python script, and use the result from the evalution?

推荐答案

您想要的是exec而不是eval.

>>> s = "x = 2"
>>> exec s
>>> x
2

当然，请不要在不受信任的字符串上使用exec ...

Of course, please don't use exec on untrusted strings ...

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