Array

v0.3

Array module for lua

Installation

The array.lua file should be dropped into an existing project and required by it.

Array = require 'array'

Example

arr = Array()

-- add
arr:add(1)
arr:push(true)
arr:insert('hello', 1)
arr:add({a=1})

-- get
ele = arr:get(1)
ele = arr[1]

-- set
arr:set(1, 'hello')
arr[1] = 'hello'

-- pop
ele2 = arr:pop()

Usage

Constructor

arr1 = Array()
arr2 = Array(1, 2, 3) -- 1 2 3

clone

clone a array

arr = Array(1, 2, 3) -- 1 2 3
clone_arr = arr:clone() -- 1 2 3

is_empty()

return true if an array is empty

arr = Array() -- 1 2 3
arr:is_empty() -- true

size()

return count of items

arr = Array(1, 2, 3) -- 1 2 3
arr:size() -- 3

get(index)

return item which position is the index

arr = Array(1, 2, 3) -- 1 2 3
arr:get(2) -- 2
arr[2] -- 2

set(index, value)

set new value which position is the index

arr = Array(1, 2, 3) -- 1 2 3
arr:set(2, 4) -- 1 4 3
arr[2] = 4 -- 1 4 3

add(item) or push(item)

add item to the end of array

arr = Array(1, 2, 3) -- 1 2 3
arr:add(4) -- 1 2 3 4
arr:push(5) -- 1 2 3 4 5

insert(item, pos)

insert item to the position

arr = Array(1, 2, 3) -- 1 2 3
arr:insert(0, 2) -- 1 0 2 3

remove(item)

remove item from array

arr = Array(1, 2, 3) -- 1 2 3
arr:remove(2) -- 1 3

remove_at(index)

remove item from array which position is the index

arr = Array(1, 2, 3) -- 1 2 3
arr:remove_at(1) -- 2 3

pop()

return the last item

arr = Array(1, 2, 3) -- 1 2 3
last_item = arr:pop() -- 3

index_of(item)

return the index of the item

arr = Array(1, 2, 3) -- 1 2 3
arr:index_of(2) -- 2

slice(start, finish)

return slice between start and finish

arr = Array(1, 2, 3) -- 1 2 3
arr2 = arr:slice(2, 3) -- 2 3

sliced(start, finish)

same as slice(start, finish), but change self rather than return new array

arr = Array(1, 2, 3) -- 1 2 3
arr:sliced(2, 3) -- 2 3

reverse()

return reversed array

arr = Array(1, 2, 3) -- 1 2 3
arr2 = arr:reverse() -- 3 2 1

reversed()

same as reverse(), but change self rather than return new array

arr = Array(1, 2, 3) -- 1 2 3
arr:reversed() -- 3 2 1

first()

return the first item in array

arr = Array(1, 2, 3) -- 1 2 3
item = arr:first() -- 1

last()

return the last item in array

arr = Array(1, 2, 3) -- 1 2 3
item = arr:last() -- 3

map(callback)

create a new array of values by mapping each value in array through a transformation function

callback(item, index)

arr = Array(1, 2, 3) -- 1 2 3
arr2 = arr:map(function (item, index)
    return item + index
end) -- 2 4 6

mapped(callback)

same as map(callback), but change self rather than return new array

arr = Array(1, 2, 3) -- 1 2 3
arr:mapped(function (item, index)
    return item + index
end) -- 2 4 6

filter(callback)

create a new array containing all elements that pass truth test

callback(item, index)

arr = Array(1, 2, 3) -- 1 2 3
arr2 = arr:map(function (item, index)
    return index % 2 == 0
end) -- 2

filtered(callback)

same as filter(callback), but change self rather than return new array

arr = Array(1, 2, 3) -- 1 2 3
arr:filtered(function (item, index)
    return index % 2 == 0
end) -- 2

reduce(callback)

applies a function against an accumulator and each value of the array to reduce it to a single value

arr = Array(1, 2, 3) -- 1 2 3
ret = arr:reduce(function (a, b)
    return a + b
end) -- 6

concat(other_array)

return a new array joining all values from the two tables passed by parameter

arr = Array(1, 2, 3) -- 1 2 3
arr2 = Array(4, 5, 6) -- 4 5 6
arr3 = arr:concat(arr2) -- 1 2 3 4 5 6

unique()

return a new array, removing duplicates values

arr = Array(1, 2, 3, 2, 3) -- 1 2 3 2 3
arr2 = arr:unique() -- 1 2 3

uniqued()

same as unique(), but change self rather than return new array

arr = Array(1, 2, 3, 2, 3) -- 1 2 3 2 3
arr:uniqued() -- 1 2 3