test_exec.py

Question

我有一个手动维护的python函数和模块列表，将由遗传算法和我希望能够反复调用这些并监视结果。

test_exec.py

import os
from random import randint

def main():
    toolList = [{'file':'test1.py', 'function':'sum_even_numbers', 'args':['list'], 'return':['int']},
                {'file':'test1.py', 'function':'get_min_even_num', 'args':['list'], 'return':['int']}   ]
    for tool in toolList:
        for i in range(0,3):
            run(tool, [randint(10,99) for j in range(1,randint(2,5))])

def run(tool, args):
    mod = __import__( os.path.basename(tool['file']).split('.')[0])
    func = getattr(mod, tool['function'])
    tool['return'] = func(args)
    print('main called ' + tool['file'] + '->' + tool['function'] + ' with ', args, ' = ', tool['return'])

main()

test1.py

def sum_even_numbers(numbers):
    return sum([i for i in numbers if i % 2 == 0])

def get_min_even_num(numbers):
    return min([i for i in numbers if i % 2 == 0])

# other code in test1.py which we dont want to execute
print('test1.py has been run' )

代码的结果：

test1.py has been run
('main called test1.py->sum_even_numbers with ', [30, 66, 25, 45], ' = ', 96)
('main called test1.py->sum_even_numbers with ', [92], ' = ', 92)
('main called test1.py->sum_even_numbers with ', [59, 73], ' = ', 0)
('main called test1.py->get_min_even_num with ', [59, 12, 61, 24], ' = ', 12)
('main called test1.py->get_min_even_num with ', [22], ' = ', 22)
('main called test1.py->get_min_even_num with ', [97, 94], ' = ', 94)

代码通过字符串调用模块中的函数来工作，但在导入期间执行整个文件。有没有更好的方法来执行此操作，以便不运行整个模块？

Answer 1

当您从模块导入内容时 - 甚至是独立的模块级函数 - python解释器具有来解析/编译整个文件，然后才能访问该函数。

在def s的情况下，这是无害的 - 它们只是被编译成函数，没有造成任何伤害。但是，有时你会有＆＃34;代码，你不想运行＆＃34;，就像你的例子中的print一样。

导入模块时阻止代码执行的规范方法是：

if __name__ == '__main__':
    # code that only gets executed when I explicitly run this module

通过字符串在外部模块中调用Python函数

test_exec.py

test1.py

1 个答案: