Sass 列表功能
Sass 列表函数
列表函数用于访问列表中的值、组合列表以及向列表添加项目。
Sass 列表是不可变的（它们不能更改）。因此，返回列表的列表函数将返回一个新列表，并且不会更改原始列表。
Sass 列表是从 1 开始的。列表中的第一个列表项位于索引 1，而不是 0。
下表列出了 Sass 中的所有列表函数：
| Function | Description & Example |
|---|---|
| append(list, value, [separator]) | Adds a single value to the end of the list. separator can be auto, comma, or space. auto is default. Example: append((a b c), d) Result: a b c d append((a b c), (d), comma) Result: a, b, c, d |
| index(list, value) | Returns the index position for the value in list. Example: index(a b c, b) Result: 2 index(a b c, f) Result: null |
| is-bracketed(list) | Checks whether the list has square brackets. Example: is-bracketed([a b c]) Result: true is-bracketed(a b c) Result: false |
| join(list1, list2, [separator, bracketed]) | Appends list2 to the end of list1. separator can be auto, comma, or space. auto is default (will use the separator in the first list). bracketed can be auto, true, or false. auto is default. Example: join(a b c, d e f) Result: a b c d e f join((a b c), (d e f), comma) Result: a, b, c, d, e, f join(a b c, d e f, $bracketed: true) Result: [a b c d e f] |
| length(list) | Returns the length of the list. Example: length(a b c) Result: 3 |
| list-separator(list) | Returns the list separator used, as a string. Can be either space or comma. Example: list-separator(a b c) Result: "space" list-separator(a, b, c) Result: "comma" |
| nth(list, n) | Returns the nth element in the list. Example: nth(a b c, 3) Result: c |
| set-nth(list, n, value) | Sets the nth list element to the value specified. Example: set-nth(a b c, 2, x) Result: a x c |
| zip(lists) | Combines lists into a single multidimensional list. Example: zip(1px 2px 3px, solid dashed dotted, red green blue) Result: 1px solid red, 2px dashed green, 3px dotted blue |