My JS Lib

A bunch of extensions to the native javascript prototypes.

Mostly a project for my own learning, but who knows? Maybe someone will find it useful.

You can play with it in the browser here.

Using

After cloning,

npm install

Run tests

npm test

Build + minify

npm run build

Documentation

Documentation is built into the tests

npm test -- --verbose

Sample output:

Number.prototype
  .isOdd() and .isEven()
    ✓ (57).isOdd() === true (2ms)
    ✓ (42).isOdd() === false
    ✓ (42).isEven() === true
    ✓ (57).isEven() === false
  .to(end[, step]) -- range function
    ✓ (10).to(1) === [] (1ms)
    ✓ (5).to(5) === []
    ✓ (1).to(10) === [1, 2, 3, 4, 5, 6, 7, 8, 9] (1ms)
    ✓ (-3).to(3) === [-3, -2, -1, 0, 1, 2]
    ✓ (1).to(10, 2) === [1, 3, 5, 7, 9]
    ✓ (1).to(5, 0) === []
    ✓ (1).to(5, -1) === []
    ✓ (1).to(5, 10) === [1] (1ms)
    ✓ (0).to(0.3, 0.1) === [0, 0.1, 0.2]
  .times(cb) -- repeatedly run a function
    ✓ (5).times(cb) -- cb is called 5 times (1ms)
    ✓ passes the number of the iteration to the callback
  .fizzbuzz() -- do fizzbuzz for one number
    ✓ (1).fizzbuzz() === 1
    ✓ (2).fizzbuzz() === 2 (2ms)
    ✓ (3).fizzbuzz() === "fizz"
    ✓ (4).fizzbuzz() === 4
    ✓ (5).fizzbuzz() === "buzz" (1ms)
    ✓ (6).fizzbuzz() === "fizz"
    ✓ (7).fizzbuzz() === 7
    ✓ (8).fizzbuzz() === 8
    ✓ (9).fizzbuzz() === "fizz"
    ✓ (10).fizzbuzz() === "buzz"
    ✓ (11).fizzbuzz() === 11 (1ms)
    ✓ (12).fizzbuzz() === "fizz"
    ✓ (13).fizzbuzz() === 13
    ✓ (14).fizzbuzz() === 14
    ✓ (15).fizzbuzz() === "fizzbuzz"

Array.prototype
  .first([n]) -- returns the first n elements
    ✓ [1, 2, 3].first() === 1 (1ms)
    ✓ [1, 2, 3].first(1) === [1]
    ✓ [1, 2, 3].first(2) === [1, 2] (1ms)
    ✓ [1, 2, 3].first(100) === [1, 2, 3]
    ✓ [].first() === undefined
    ✓ [].first(1) === []
    ✓ [].first(10) === [] (1ms)
  .rest() -- returns everything but the first element
    ✓ [1, 2, 3, 4, 5].rest() === [2, 3, 4, 5]
    ✓ [1].rest() === []
    ✓ [].rest() === []
  .last([n]) -- returns the last n elements
    ✓ [1, 2, 3, 4, 5].last() === 5 (1ms)
    ✓ [1, 2, 3, 4, 5].last(1) === [5]
    ✓ [1, 2, 3, 4, 5].last(2) === [4, 5]
    ✓ [1, 2, 3].last(100) === [1, 2, 3] (1ms)
    ✓ [].last() === undefined
    ✓ [].last(1) === [] -- [].last(100) === []
  .sample([n]) -- returns n random elements
    ✓ returns a random element when passed no args (3ms)
    ✓ returns an array of randomly selected items when passed a number (1ms)
  .chunk(n) -- breaks an array in n-sized chunks
    ✓ [1, 2, 3].chunk(1) === [[1], [2], [3]]
    ✓ [1, 2, 3, 4, 5, 6].chunk(2) === [[1, 2], [3, 4], [5, 6]]
    ✓ [1, 2, 3, 4, 5, 6].chunk(5) === [[1, 2, 3, 4, 5], [6]] (1ms)
    ✓ [1, 2, 3].chunk(4) === [[1, 2, 3]]
  .unique() -- removes duplicate values
    ✓ [1, 2, 3, 1, 2, 3].unique() === [1, 2, 3]
    ✓ [5, 7, 9].unique() === [5, 7, 9]
  .without(ele1[, ele2[, ...]]) -- removes element(s) from an array
    ✓ [1, 2, 3, 4, 5].without(3) === [1, 2, 4, 5] (1ms)
    ✓ [1, 2, 3, 4, 5].without(2, 3, 4) === [1, 5]
    ✓ [1, 2, 3, 4, 5].without(200) === [1, 2, 3, 4, 5]
  .flatten() -- flattens an array
    ✓ [[1, 2], [3, 4], [5]].flatten() === [1, 2, 3, 4, 5]
    ✓ [[1, [2, [3, [4, [5]]]]]].flatten() === [1, 2, 3, 4, 5]
    ✓ [1, 2, 3, 4, 5].flatten() === [1, 2, 3, 4, 5] (1ms)
  .dropIf(fn) -- the opposite of .filter()
    ✓ [1, 2, 3, 4, 5].dropIf(n => n === 1) === [2, 3, 4, 5]
    ✓ [1, 2, 3, 4, 5].dropIf((n, i) => n == 3 || i == 1) === [1, 4, 5] (1ms)

String.prototype
  .chars()
    ✓ "qwerty".chars() === ["q", "w", "e", "r", "t", "y"] (1ms)
  .capitalize() -- uppercases the first letter
    ✓ "asdf".capitalize() === "Asdf" (1ms)
    ✓ "ABC".capitalize() === "ABC" (1ms)
    ✓ "123abc".capitalize() === "123abc"
  .lines() -- splits a string by newlines
    ✓ "line one\nline two\nline three".lines() === ["line one", "line two", "line three"]
  .reverse() -- reverses a string
    ✓ "abc".reverse() === "cba"
  .without(str1[, str2[, ...]]) -- removes instances of given string(s)
    ✓ "abcabcabc".without("bc") === "aaa"
    ✓ "mary had a little lamb, a little lamb, a little lamb".without("little", "lamb") === "mary had a  , a  , a  "
    ✓ "abc".without("d") === "abc" (1ms)