生成替换字符串的所有组合

Question

我有一个相当具体的编程问题已经困扰了我几个星期了，我相信这是正确的地方。

我需要一个函数，它可以生成各种子字符串的所有组合，例如，替换为更大的字符串；

thisfunction([['Hello','hi'],['Goodbye','bye'],['Hello','goodbye']], "This is a string that says Hello and Goodbye and Hello again")

应该返回

["String that says Hello, Goodbye and Hello again",
"String that says hi and Goodbye and Hello again",
"String that says hi and bye and Hello again",
"String that says Hello and bye and Hello again",
"String that says Hello, Goodbye and goodbye again",
"String that says hi and Goodbye and goodbye again",
"String that says hi and bye and goodbye again",
"String that says Hello and bye and goodbye again",]

我用正则表达式和替换函数尝试了各种策略，但没有成功
感谢所有想法！

Answer 1

您可以使用itertools.product、str.format 来实现类似：

from itertools import product

def thisfunction(lst, s):
    for p in product(*lst):
        yield s.format(*p)

>>> list(thisfunction([['Hello','hi'],['Goodbye','bye'],['Hello','goodbye']], 
                      "This is a string that says {} and {} and {} again"))
['This is a string that says Hello and Goodbye and Hello again',
 'This is a string that says Hello and Goodbye and goodbye again',
 'This is a string that says Hello and bye and Hello again',
 'This is a string that says Hello and bye and goodbye again',
 'This is a string that says hi and Goodbye and Hello again',
 'This is a string that says hi and Goodbye and goodbye again',
 'This is a string that says hi and bye and Hello again',
 'This is a string that says hi and bye and goodbye again']

Answer 2

from itertools import product

def thisfunction(lst, s):
    for first, *rest in lst:
        s = s.replace(first, '{}', 1)
    for p in product(*lst):
        yield s.format(*p)

print(list(thisfunction([['Hello','hi'],['Goodbye','bye'],['Hello','goodbye']], "This is a string that says Hello and Goodbye and Hello again")))