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aerospike udf 使用之 list     所属分类 aerospike 浏览量 9
https://www.aerospike.com/docs/udf/api/list.html

The list modules introduces a List type and functions to Lua. 
It provides a consistent interface for working with a sequence of values, which is not provided by Lua Tables.

列表类型 , 为处理一组值提供一致的接口

Aerospike Lua list objects are usually returned in Aerospike functions, 
and set as values in the Aerospike database.

local l = list()

create an empty List with a specific initial capacity
local l = list.create(100)

local l = list {1,2,3,4}

To create an empty List with an initial capacity of 50 and a step size of 25
local l = list.create(50, 25)

function list.size(l: List): Integer

function list.iterator(l: List): iterator


local l = list {1,2,3}

for value in list.iterator(l) do
    info("%s", tostring(value))
end


指定位置insert
function list.insert(l: List, i: Integer, v: Val): nil

i – The list index at which to insert the value.
v – The value to insert into the list.

local l = list {1,2,3,4}
List(1,2,3,4)

list.insert(l, 3, 55)
List(1,2,55,3,4)

尾部Insert
function list.append(l: List, v: Val): nil

头部Insert
function list.prepend(l: List, v: Val): nil

Select the first n elements of the List
function list.take(l: List, n: Integer): List
n – The number of values to select from the beginning of the list.


删除指定位置元素
Remove an element from the List at a specified position.
function list.remove(l: List, i: Integer): nil
i – The index of the list value to remove.


Select all elements except the first n elements of the List.
function list.drop(l: List, n: Integer): List
n – The number of values to skip from the beginning of the list.

A new list containing the values after the first n values of the list l.

local l = list {1,2,3}
List(1,2,3)

list.drop(l, 2)
List(3)


截掉指定位置之后的元素
Remove all elements at and beyond a specified position in the List.

function list.trim(l: List, i: Integer): nil
i – The index from which to trim the list.
local l = list {1,2,3,4,5}
List(1,2,3,4,5)

list.trim(l, 4)
List(1,2,3)

Create a new List as a shallow copy of another List. All elements are references to the elements of the original List, not copies.
function list.clone(l: List): List


list.concat()
Append all elements of one list, in order, to another list.
function list.concat(l1: List, l2: List): nil
l1 – The List to append to.
l2 – The List to be appended.

Merge the elements of given two lists and return the combined list.
function list.merge(l1: List, l2: List): List
l1 – One of the List to be merged
l2 – Another List to be merged

注意 concat  和 merge 的区别 

concat 直接追到第一个列表
merge  合并两个列表,返回新的列表

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