functional-lua

Simple Implementation of Functional Programming Resources

Functional.lua is a module written in Lua which implements some functional programming features such as map, filter, reduce, any, all (of Haskell and Python) with feature range and rangerandom (inspired by Python) to generate lists (without support list comprehensions), and replicate to repeat elements of lists (itertools repeat the Python).

Functions:

functional.range(from[, to[, step]]) -> table
functional.map(f, ...) -> table
functional.reduce(x[, op]) -> number
functional.filter(f, x) -> table
functional.rangerandom(max[, m, [n]]) -> table
functional.any(f, x) -> boolean
functional.all(f, x) -> boolean
functional.replicate(x,y) -> table

-- Function range: Generate list of elements

range(from[, to[, step]])

Examples:

range(10) => {1,2,3,4,5,6,7,8,9,10}
range(2,5) => {2,3,4,5}
range(-2,4,2) => {-2,0,2,4}

param from: number
param to: number (optional)
param step: number (optional, default: 1)
return: table

-- Function rangerandom: Generate list pseudo-random

rangerandom(max[, m,[ n]])

Examples:

rangerandom(2) => {0.039280343353413, 0.43763759659493}
rangerandom(5,-10,0) => {-9,0,-2,5,-3}

param max: number of elements
param m, n: interval of choice random m, n
return: table

-- Function map: Applies the function f on each table passed as argument

map( f, ...)

Example:

f = function(a,b) return a + b end
x, y = {2,4}, {2,4}
map(f,x,y) ==> table: {4,16}

param f: function
param ... : multiples parameters of lists(table)
return: table or nil

-- Function reduce: Reduce table according to the operation defined

reduce(x[, op])

Example:

reduce({2,4,6}}) => number: 12
reduce({2,4,6}, '*') => number: 48

param x: table
param op: string, operation mathematic: +,-,*,/,^ (default: +)
return: number

-- Function filter: Creates a list starting from x where x a for each function f is true

filter(f, x)

Example:

f = function(a) if type(a) == 'number' then return true end return false end
filter(f, {'aa','bc',123, '1567', 5, 8, 0, 'a'}) -> {123, 5, 8, 0}

param: f: function
param: x: table
return: table

--Function any: Returns true if any element of x is true for the function f(x)

any(f, x)

Example:

function f(a) if type(a) == 'number' then return true end return false end
any(f, {2,3,4,5}) -> true
any(f, {2,3,4,'aba'}) - -> true
any(f, {'lol', 'test', '2'}) -> false

param f: function
param x: table
return: boolean

--Function all: Returns true if all element of x is true for the function f(x)

all(f, x)

Example:

function f(a) if type(a) == 'number' then return true end return false end
all(f, {2,3,4,5}) -> true
all(f, {2,3,4,'aba'}) - -> false
all(f, {'lol', 'test', '2'}) -> false

param f: function
param x: table
return: boolean

--Function replicate: Generates a list of elements x of y

replicate(x, y)

Example:

replicate('a',5) -> {'a', 'a', 'a', 'a', 'a'}
replicate({2}, 3) -> {{2}, {2}, {2}}
replicate(2, 4) -> {2, 2, 2, 2}

param x: number, string, table, function
param y: number > 0
return: table