Extend JavaScript classes in base of Ruby methods

Array

.first()

Returns the first element of the array. If the array is empty, the first form returns undefined. See also #last for the opposite effect.

var dummy = ['a', 'b', 'c', 'd'];
dummy.first(); #=> `a`

.last()

Returns the last element of self. If the array is empty, the first form returns undefined.

var dummy = ['a', 'b', 'c', 'd'];
dummy.last(); #=> 'd'

.empty()

Returns true if self contains no elements.

[].empty() #=> true

.clear()

Removes all elements from self.

var dummy = ['a', 'b', 'c', 'd'];
dummy.clear(); #=> []

.size()

Alias for .length.

.sample()

Choose a random element or n random elements from the array.

If the array is empty the first form returns undefined.

var dummy = ['a', 'b', 'c', 'd'];
dummy.sample(); #=> 'c'

.compact()

Returns a copy of self with all undefined or null elements removed.

var dummy = ['a', undefined, null, 'd'];
dummy.compact(); #=> ['a', 'd']

.include()

Returns true if the given object is present in self (that is, if any element === object), otherwise returns false.

var dummy = ['a', 'b', 'c', 'd'];
dummy.include('b') #=> true

.take()

Returns first n elements from the array.

var dummy = ['a', 'b', 'c', 'd'];
dummy.take(2) #=> ['a', 'b']

Number

.times()

Iterates the given block int times, passing in values from zero to int - 1.

(5).times(function (i) {
  console.log(i);
});
#=> 0 1 2 3 4

.upto()

Iterates the given block, passing in integer values from int up to and including limit.

(1).upto(5, function (i) {
  console.log(i);
});
#=> 1 2 3 4 5

.downto()

Iterates the given block, passing decreasing values from int down to and including limit.

(5).downto(1, function (i) {
  console.log(i);
});
#=> 5 4 3 2 1