如何使用单行将列表/元组转换为 python 中的空格分隔字符串？

Question

I tried doing:

str = ""
"".join(map(str, items))

but it says str object is not callable. Is this doable using a single line?

Answer 1

Use string join() method.

List:

>>> l = ["a", "b", "c"]
>>> " ".join(l)
'a b c'
>>> 

Tuple:

>>> t = ("a", "b", "c")
>>> " ".join(t)
'a b c'
>>> 

Non-string objects:

>>> l = [1,2,3]
>>> " ".join([str(i) for i in l])
'1 2 3'
>>> " ".join(map(str, l))
'1 2 3'
>>> 

Answer 2

The problem is map need function as first argument.

Your code

str = ""
"".join(map(str, items))

Make str function as str variable which has empty string.

Use other variable name.

Answer 3

Your map() call isn't working because you overwrote the internal str() function. If you hadn't done that, this works:

In [25]: items = ["foo", "bar", "baz", "quux", "stuff"]

In [26]: "".join(map(str, items))
Out[26]: 'foobarbazquuxstuff'

Or, you could simply do:

In [27]: "".join(items)
Out[27]: 'foobarbazquuxstuff'

assuming items contains strings. If it contains int s, float s, etc., you'll need map() .

Answer 4

Try:

>>> items=[1, 'a', 2.3, (1, 2)]
>>> ' '.join(str(i) for i in items)
'1 a 2.3 (1, 2)'

Answer 5

Alternatively, you can use repr function when mapping, which is similar to str (but more specialized behavior:

A good resource: What is the difference between str and repr ?

items=[1, 'a', 2.3, (1, 2)]
' '.join(map(repr, items))