big-brain.js

Ranges

      const { range } = require('big-brain.js');

      /**
       * Can be used to make loops
       */
      for (let i of range(3)) {
        console.log(`hello from loop ${i}`);
      }
      // hello from loop 0
      // hello from loop 1
      // hello from loop 2

      /**
       * Ranges to Arrays
       */
      Array.from(range(12));
      // [ 0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11]

      Array.from(range(11, 18));
      // [ 11, 12, 13, 14, 15, 16, 17 ]

      Array.from(range(10, 0));
      // [ 10, 9, 8, 7, 6, 5, 4, 3, 2, 1 ]

      /**
       * Unlike Python ranges, step is always a positive number
       */
      Array.from(range(0, 20, 2));
      // [0,  2,  4,  6,  8, 10, 12, 14, 16, 18]
            

Random Integers

(without having to write the function yourself each time (I always forget how it goes :c))

      const { randInt } = require('big-brain.js');

      randInt(100);
      // 40

      randInt(1, 5);
      // 3

      /**
       * Random enough for general purpose
       */
      let ints = [];
      for (let i of range(10000000)) {
        ints.push(randInt(1, 11));
      }

      /**
       * Should be 5.5
       */
      ints.reduce((previous, current) => current += previous) / ints.length;
      // 5.5007626
            

Random choice from array

      const { randChoice } = require('big-brain.js');

      const presidents = ['George Washington', 'John Adams', 'Thomas Jefferson', 'James Madison', 'James Monroe'];

      randChoice(presidents);
      // 'John Adams'
            

Shuffle arrays

(this doesn't mutate the array)

      const { shuffleArray } = require('big-brain.js');

      let presidents = ['George Washington', 'John Adams', 'Thomas Jefferson', 'James Madison', 'James Monroe'];

      shuffleArray(presidents);
      // ['James Monroe', 'George Washington', 'James Madison', 'John Adams', 'Thomas Jefferson']

      /**
       * Note that the original array is still in order
       */
      presidents
      // ['George Washington', 'John Adams', 'Thomas Jefferson', 'James Madison', 'James Monroe']

      /**
       * To permanently rearrange, reassign:
       */
      presidents = shuffleArray(presidents);
      // ['James Monroe', 'Thomas Jefferson', 'George Washington', 'John Adams', 'James Madison']