13.11. Sass list function

Function	Description & example
`append(list, value, [separator])`	Add a single value value to the end of the list. Separator is a delimiter and is automatically detected by default, or specified as a comma or space. 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 of the element value in the list. Example: index (a b c, b) result: 2 index (a b c, f) result: null
`is-bracketed(list)`	Determine whether there are brackets in the list Example: is-bracketed ( [a b c] ) result: true is-bracketed (a b c) result: false
`join(list1, list2, [separator, bracketed])`	Merge the two lists and add the list list2 to the end of the list list1. Separator is a delimiter and is automatically detected by default, or specified as a comma or space. By default, bracketed automatically detects whether there are square brackets, which can be set to true or false. 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 delimiter type of a list. It can be a space or a comma. Example: list-separator (a b c) result: “space” list-separator (a, b, c) result: “comma”
`nth(list, n)`	Gets the value of item n. Example: nth (a b c, 3) result: C
`set-nth(list, n, value)`	Set the value of item n of the list to value. Example: set-nth (a b c, 2, x) result: a x c
`zip(lists)`	Reassemble multiple lists into a new multi-dimensional list with the same index values. Example: zip (1px 2px 3px, solid dashed dotted, red green blue) result: 1px solid red, 2px dashed green, 3px dotted blue

Function

Description & example

append(list, value, [separator])

Add a single value value to the end of the list. Separator is a delimiter and is automatically detected by default, or specified as a comma or space.

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 of the element value in the list.

Example: index (a b c, b) result: 2 index (a b c, f) result: null

is-bracketed(list)

Determine whether there are brackets in the list

Example: is-bracketed ( [a b c] ) result: true is-bracketed (a b c) result: false

join(list1, list2, [separator, bracketed])

Merge the two lists and add the list list2 to the end of the list list1. Separator is a delimiter and is automatically detected by default, or specified as a comma or space. By default, bracketed automatically detects whether there are square brackets, which can be set to true or false.

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 delimiter type of a list. It can be a space or a comma.

Example: list-separator (a b c) result: “space” list-separator (a, b, c) result: “comma”

nth(list, n)

Gets the value of item n.

Example: nth (a b c, 3) result: C

set-nth(list, n, value)

Set the value of item n of the list to value.

Example: set-nth (a b c, 2, x) result: a x c

zip(lists)

Reassemble multiple lists into a new multi-dimensional list with the same index values.

Example: zip (1px 2px 3px, solid dashed dotted, red green blue) result: 1px solid red, 2px dashed green, 3px dotted blue

最近几年来，地理信息系统无论是在理论上还是应用上都处在一个飞速发展的阶段。 GIS被应用于多个领域的建模和决策支持，如城市管理、区划、环境整治等等，地理信息成为信息时代重要的组成部分之一； “数字地球”概念的提出，更进一步推动了作为其技术支撑的GIS的发展。与此同时，一些学者致力于相关的理论研究，如空间感知、空间数据误差、空间关系的形式化等等。这恰好说明了地理信息系统作为应用技术和学科的两个方面，并且这两个方面构成了相互促进的发展过程。