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Create a cond function that takes 2 arguments:

1. An matrix in the format:

[
  [firstCondition, firstCallback],
  [secondCondition, secondCallback],
  ...
]

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/*
 * imap lazily maps an interable.
 * @param ref   Either an iterable or an iterator
 * @param fn    Map function
 *
 * It works by always returning a new iterator so that
 * you can chain other imaps without looping once more
 * over the same array!
 *
 * Since iterators are returned, to start the real mapping

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const validPost = post =>
  post.title && post.title.length > 10 && post.content
  
const posts =
[ {title: 'short'}
, {title: 'fairly long', content: 'Foobar'}
, {title: 'yet another', content: 'fixture'}
]

const validPosts = posts.every(validPost)

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const range = (start, end) =>
  Array.from({length: end - start}, (_, i) => start + i)

const divides = x => y =>
  x % y === 0
  
const prime = n => {
  if (n < 2)
    return false
  if (n === 2)

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const checkAndLog = x => {
  console.log('passed by', x)
  return Number.isInteger(x)
}

const xs = ['a', 1, 2, 3, 4]
const ys = ['a', 'b', 'c', 'd', 'e']

const xsHasinteger = xs.some(checkAndLog)
// passed by a

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const checkAndLog = x => {
  console.log('passed by', x)
  return Number.isInteger(x)
}

const xs = [1, 2, 3, 4, 5]
const ys = [6, 7, 'a', 9, 10]

const areXsIntegers = xs.every(checkAndLog)
// passed by 1

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const xs = ['a', 'b', 'c', 'd', 5]
const ys = ['a', 'b', 'c', 'd', 'e']

const xsHasinteger = xs.some(Number.isInteger)
const ysHasinteger = ys.some(Number.isInteger)

console.log(xsHasinteger) // true
console.log(ysHasinteger) // false

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const xs = [1, 2, 3, 4, 5]
const ys = [1, 2, 'a', 4, 5]

const areXsIntegers = xs.every(Number.isInteger)
const areYsIntegers = ys.every(Number.isInteger)

console.log(areXsIntegers) // true
console.log(areYsIntegers) // false

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const add = (x, y) => x + y
const sub = (x, y) => x - y

console.log('10 + 3 - 4 =', sub( add(10, 3), 4 ) )

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const add = x => y => x + y
const sub = x => y => x - y

console.log('10 + 3 - 4 =', sub( add(10)(3) )(4) )