Question

我有一份清单清单：

array = ['there is nothing','there is everything,',['there is','where']]

这是一小段代码：

str2 = ""
for item in array:
    str2 += "".join(char for char in item)

给出：

'there is nothingthere is everything,there iswhere'

我怎么可能在外部列表的每个项目和内部列表之间添加一个空格？

预期的输出字符串为：

'there is nothing there is everything, there is where'

我提到了问题one和two，虽然这个问题在我的案例中起作用，但第一个问题是：

str2=""
lst = [' {}'.format(elem) for elem in array]
for item in lst:
    str2 += "".join(char for char in item)

输出：

" there is nothing there is everything, ['there is', 'where']"

而第二个不适用于单词。

Answer 1

我会定义一个可以处理任意嵌套字符串列表的函数：

array = ['there is nothing','there is everything,',['there is','where']]

def concat_string(array):
    ret = ""
    for item in array:
        if isinstance(item,list):
            ret += concat_string(item)
        else:
            ret += item + " "

    return ret

print concat_string(array)

Answer 2

怎么样：

array = ['there is nothing','there is everything,',['there is','where']]
s = ''
for i in array:
    if isinstance(i, list):
        for j in i:
            s = ' '.join((s, j)) if s != '' else j
    else:
        s = ' '.join((s, i)) if s != '' else i
print(s)

Answer 3

我认为最好的方法是先将列表展平，然后按空格加入。

import collections
def flatten(foo):
    for x in foo:
        if isinstance(x, collections.Iterable) and not isinstance(x, str):
            for y in flatten(x):
                yield y
        else:
            yield x

my_sentence = " ".join(flatten(array))

或者，您可以使用@bhat irshad所述的单行解决方案，但它不适用于任意嵌套

In [1]: array = ['there is nothing','there is everything,',['there is','where']]

In [2]: " ".join([" ".join(s) if isinstance(s,list) else s for s in array])
Out[2]: 'there is nothing there is everything, there is where'

Answer 4

应该是：

array = ['there is nothing','there is everything,',['there is','where']]  
newstring = ''
for a in array :
    if type( a ) is str :
        newstring += a + " "
    else :
        newstring += ' '.join( a )

它几乎可能是：' '.join( [ ''.join(x) for x in array ] )

你也可以使用三元：

array = ['there is nothing','there is everything,',['there is','where']]  
newstring = ''
for a in array :
    newstring += a + " " if type( a ) is str else ' '.join( a )

Answer 5

使用您的问题1，以下将是一个通用但不是有效的解决方案。 1.为列表的所有元素添加空格 2.将它们与我们的小代码合并。 3.从两端修剪空格 4.删除可能已创建的重复空格。

加入嵌套的字符串列表

5 个答案: