将python代码移植到javascript

Question

indices[i:] = indices[i+1:] + indices[i:i+1]

希望有人帮忙.

Answer 1

我对Python很新,但如果我正确理解代码,它会将给定偏移量的列表重建为偏移+ 1后面的每个项目和偏移量下的项目.

运行它似乎证实了这一点:

>>> indices = ['one','two','three','four','five','six']
>>> i = 2
>>> indices[i:] = indices[i+1:] + indices[i:i+1]
>>> indices
['one', 'two', 'four', 'five', 'six', 'three']

在Javascript中可以写:

indices = indices.concat( indices.splice( i, 1 ) );

相同的整个序列将会:

>>> var indices = ['one','two','three','four','five','six'];
>>> var i = 2;
>>> indices = indices.concat( indices.splice( i, 1 ) );
>>> indices
["one", "two", "four", "five", "six", "three"]

这是因为splice对数组具有破坏性,但返回已删除的元素,然后可以将其传递给concat.