如何提取字符串之前的单词？

Question

I have several strings like this:

mylist = ['pearsapple','grapevinesapple','sinkandapple'...]

I want to parse the parts before apple and then append to a new list:

new = ['pears','grapevines','sinkand']

Is there a way other than finding starting points of 'apple' in each string and then appending before the starting point?

Answer 1

By using slicing in combination with the index method of strings.

>>> [x[:x.index('apple')] for x in mylist]
['pears', 'grapevines', 'sinkand']

You could also use a regular expression

>>> import re
>>> [re.match('(.*?)apple', x).group(1) for x in mylist]
['pears', 'grapevines', 'sinkand']

I don't see why though.

Answer 2

我希望apple这个词将是固定的（固定长度的词），然后我们可以使用：

second_list = [item[:-5] for item in mylist]

Answer 3

If some elements in the list don't contain 'apple' at the end of the string, this regex leaves the string untouched:

>>> import re
>>> mylist = ['pearsapple','grapevinesapple','sinkandapple', 'test', 'grappled']
>>> [re.sub('apple$', '', word) for word in mylist]
['pears', 'grapevines', 'sinkand', 'test', 'grappled']

Answer 4

By also using string split and list comprehension

new = [x.split('apple')[0] for x in mylist]
['pears', 'grapevines', 'sinkand']

Answer 5

One way to do it would be to iterate through every string in the list and then use the split() string function.

for word in mylist:
    word = word.split("apple")[0]