functioner

0.2.1 • Public • Published

functioner

A Node.js module containing a set of higher order functions

functioner is a library mainly focused on higher-order functions, like the map, filter, and forEach functions used on arrays.

This functional programming methodology can be more easily embraced with a large set of higher-order functions allowing more compact anonymous function creation.

functioner contains a set of assertion functions, a lot like other libraries; however, these functions are higher-order which allows for unique usage in modules like dependon.

Install

$ npm install functioner

Usage

assert

var f = require('functioner').assert;
var numbers = [0, 1, 2, 3, 4, 5];
 
var lessThan3 = numbers.filter(f.lessThan(3));
//    => [ 0, 1, 2 ]
 
var odds = numbers.filter(f.odd);
//    => [1, 3, 5]
 
var between1and4 = numbers.filter(f.between(1, 4));
//    => [2, 3]
var types = [1, 'abc', {}, [1,2,3], false];
 
var iters = types.filter(f.type('iterable'));
//    => [ 'abc', [ 1, 2, 3 ] ]
  • type(string): returns a function that checks the types variables given to the function.
  • greaterThan(number): returns a function that checks if a number is greater than the original number given.
  • gt(number): short notation for greaterThan
  • greaterThanOrEqualTo(number): returns a function that checks if a number is greater than or equal to the original number given.
  • gte(number): short notation for greaterThanOrEqualTo
  • lessThan(number): returns a function that checks if a number is less than the original number given.
  • lt(number): short notation for lessThan
  • lessThanOrEqualTo(number): returns a function that checks if a number is less than or equal to the original number given.
  • lte(number): short notation for lessThanOrEqualTo
  • equalTo(value): returns a function that checks if a given value is equal to the original.
  • eq(value): short notation for equalTo
  • null(value): returns true if value equals null, false otherwise.
  • undefined(value): returns true if value equals undefined, false otherwise.
  • assigned(value): returns true if value does not equal undefined, false otherwise.
  • has(prop): returns a function that returns true if a given object has the property initially given.
  • includes(value): returns a function that returns true if a given array has the value initially specified.
  • contains(substring): returns a function that returns true if a given string has the substring initially given.
  • match(regex): returns a function that returns true if a given string matches a given regular expression.
  • positive(number): returns true if value is greater than 0, false otherwise.
  • negative(number): returns true if value is less than 0, false otherwise.
  • zero(number): returns true if value is equal to 0, false otherwise.
  • infinity(number): returns true if value is equal to Infinity, false otherwise.
  • finite(number): returns true if value is not equal to Infinity, false otherwise.
  • between(number, number): returns a function that returns true, if a given value is between the two numbers initially given.
  • even(number): returns true if value is even, false otherwise.
  • odd(number): returns true if value is odd, false otherwise.

math

var f = require('functioner').math;
var numbers = [0, 1, 2, 3, 4];
 
var add2 = numbers.map(f.add(2));
//    => [2, 3, 4, 5, 6]
 
var clamped = numbers.map(f.clamp(1, 3));
//    => [ 1, 1, 2, 3, 3 ]
 
var scaled = numbers.map(f.scale(0, 4, 0, 1));
//    => [ 0, 0.25, 0.5, 0.75, 1 ]
  • add(number): returns a function that adds the number given to any value given to the function.
  • subtract(number): returns a function that subtracts the number given to any value given to the function.
  • divide(number): returns a function that divides any number given to the function by the number initially given.
  • multiply(number): returns a function that multiplies any number given to the function by the number initially given.
  • pow(number): returns a function that takes the power of any number given to the function to the exponent of the number initially given.
  • sum(function): takes a function and returns a function that calculates the sum from the given parameters from n0 to n
  • scale(inMin, inMax, outMin, outMax): returns a function that scales a the number given, according to the in range and out range.
  • clamp(min, max): returns a function that clamps the value given in the range initially given.
  • compose(...functions): returns a function composed of all the functions given, like so: f0(f1(f2(fn)))

extras

  • accessor(string): returns a function that gives the value at an objects has. Example: accessor('length')(str) would return the length of str.
  • index(integer): returns a function that returns the index given of a given array.
  • print(value): console.log(value)

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Install

npm i functioner

Weekly Downloads

1

Version

0.2.1

License

MIT

Last publish

Collaborators

  • craigh2013