Question

说我有一堆字符串，可以以pineapple，ham或grapefruit结尾。生成“剥离字符串”列表的最佳方法是什么，它与原始字符串完全相同，除非字符串以pineapple结尾，pineapple将从末尾剪裁，并且如果字符串以ham结尾，ham会被修剪吗？

例如，假设我的输入是

["I really like pineapple",
"I don't like ham or grapefruit",
"Today I ate a lot of ham",
"but I also ate a lot of grapefruit"]

然后输出应为

["I really like",
"I don't like ham or grapefruit",
"Today I ate a lot of",
"but I also ate a lot of grapefruit"]

Answer 1

似乎是re的工作。只需在表达式的末尾添加一个行尾锚点，使其仅在末尾处为子。

import re

stuff = ["I really like pineapple", "I don't like ham or grapefruit", "Today I ate a lot of ham", "but I also ate a lot of grapefruit"]

[re.sub(r'(pineapple|ham)$','',s).strip() for s in stuff]
Out[7]: 
['I really like',
 "I don't like ham or grapefruit",
 'Today I ate a lot of',
 'but I also ate a lot of grapefruit']

（我添加了额外的strip()来清理任何剩余的空格）

要使用任意字符串列表执行此操作，它将如下所示：

re.sub(r'({})$'.format('|'.join(arbitrary_list_of_strings)),'',s)...

Answer 2

In [3]: L = ["I really like pineapple",
   ...: "I don't like ham or grapefruit",
   ...: "Today I ate a lot of ham",
   ...: "but I also ate a lot of grapefruit"]


In [4]: suffixes = 'pineapple ham grapefruit'.split()

In [5]: for i in range(len(L)):
   ...:     while any(L[i].endswith(suffix) for suffix in suffixes):
   ...:         for suffix in suffixes:
   ...:             if L[i].endswith(suffix):
   ...:                 L[i] = L[i][:-len(suffix)]
   ...:                 break
   ...:             

In [6]: L
Out[6]: 
['I really like ',
 "I don't like ham or ",
 'Today I ate a lot of ',
 'but I also ate a lot of ']

如果您想清理那些额外的空白，可以这样做：

In [7]: L = ["I really like pineapple",
"I don't like ham or grapefruit",
"Today I ate a lot of ham",
"but I also ate a lot of grapefruit"]

In [8]: for i in range(len(L)):
    while any(L[i].endswith(suffix) for suffix in suffixes):
        for suffix in suffixes:
            if L[i].endswith(suffix):
                L[i] = L[i][:-len(suffix)-1]
                break
   ...:             

In [9]: L
Out[9]: 
['I really like',
 "I don't like ham or",
 'Today I ate a lot of',
 'but I also ate a lot of']

请注意，这也会杀死目标后缀的任何重复出现：

In [10]: L = ["I really like pineapple pineapple",
"I don't like ham or grapefruit",
"Today I ate a lot of ham",
"but I also ate a lot of grapefruit"]

In [11]: for i in range(len(L)):
    while any(L[i].endswith(suffix) for suffix in suffixes):
        for suffix in suffixes:
            if L[i].endswith(suffix):
                L[i] = L[i][:-len(suffix)-1]
                break
   ....:             

In [12]: L
Out[12]: 
['I really like',
 "I don't like ham or",
 'Today I ate a lot of',
 'but I also ate a lot of']

如何为任意字符串实现rstrip？

2 个答案: