length获取字符串、列表、Map等的长度：

> length([])
0
> length(["pkslow"])
1
> length(["pkslow", "com"])
2
> length({pkslow = "com"})
1
> length("pkslow")
6

lookup(map, key, default)根据key值在map中找到对应的value值，如果没有则返回默认值：

> lookup({name = "Larry", age = 18}, "age", 1)
18
> lookup({name = "Larry", age = 18}, "myAge", 1)
1

matchkeys(valueslist, keyslist, searchset)对key值进行匹配。匹配到key值后，返回对应的Value值。

> matchkeys(["a", "b", "c", "d"], [1, 2, 3, 4], [2, 4])
tolist([
  "b",
  "d",
])

merge合并Map，key相同的会被最后的覆盖：

> merge({name = "Larry", webSite = "pkslow.com"}, {age = 18})
{
  "age" = 18
  "name" = "Larry"
  "webSite" = "pkslow.com"
}
> merge({name = "Larry", webSite = "pkslow.com"}, {age = 18}, {age = 13})
{
  "age" = 13
  "name" = "Larry"
  "webSite" = "pkslow.com"
}

one取集合的一个元素，如果为空则返回null；如果只有一个元素，则返回该元素；如果多个元素，则报错：

> one([])
null
> one(["pkslow"])
"pkslow"
> one(["pkslow", "com"])
?
│ Error: Invalid function argument
│ 
│   on <console-input> line 1:
│   (source code not available)
│ 
│ Invalid value for "list" parameter: must be a list, set, or tuple value with either zero or one elements.
?

range生成顺序列表：

range(max)
range(start, limit)
range(start, limit, step)

> range(3)
tolist([
  0,
  1,
  2,
])
> range(1, 6)
tolist([
  1,
  2,
  3,
  4,
  5,
])
> range(1, 6, 2)
tolist([
  1,
  3,
  5,
])

reverse反转列表：

> reverse([1, 2, 3, 4])
[
  4,
  3,
  2,
  1,
]

setintersection对set求交集：

> setintersection([1, 2, 3], [2, 3, 4], [2, 3, 6])
toset([
  2,
  3,
])

setproduct列出所有组合可能：

> setproduct(["Larry", "Harry"], ["Deng", "Potter"])
tolist([
  [
    "Larry",
    "Deng",
  ],
  [
    "Larry",
    "Potter",
  ],
  [
    "Harry",
    "Deng",
  ],
  [
    "Harry",
    "Potter",
  ],
])

setsubtract：set的减法

> setsubtract([1, 2, 3], [3, 4])
toset([
  1,
  2,
])

# 求不同
> setunion(setsubtract(["a", "b", "c"], ["a", "c", "d"]), setsubtract(["a", "c", "d"], ["a", "b", "c"]))
[
  "b",
  "d",
]

setunion：set的加法

> setunion([1, 2, 3], [3, 4])
toset([
  1,
  2,
  3,
  4,
])

slice(list, startindex, endindex)截取列表部分，包括startindex，但不包括endindex：

> slice(["a", "b", "c", "d", "e"], 1, 4)
[
  "b",
  "c",
  "d",
]

sort对列表中的字符串进行排序，要注意如果输入的是数字，会先转化为字符串再排序：

> sort(["larry", "pkslow", "com", "deng"])
tolist([
  "com",
  "deng",
  "larry",
  "pkslow",
])
> sort([3, 6, 1, 9, 12, 79, 22])
tolist([
  "1",
  "12",
  "22",
  "3",
  "6",
  "79",
  "9",
])

sum求和：

> sum([3, 1.2, 9, 17.3, 2.2])
32.7

transpose对Map的key和value进行换位：