• Requires node version 10.0.0 or higher.

npm install

Implement each function in the following order. Avoid using native JavaScript implementations when possible.

When you begin working on a problem, you can enable the tests with the command:

npm run enable [problem]

and enable the challenge mode with the command:

npm run enable:challenge [problem]

The function is complete when all tests are passing. To run the test suite enter the command:

npm test
# or
npm test:watch

• add
• subtract
• inc
• dec
• multiply
• divide
• negate
• max
• min

• each
• filter
• reject
• keys
• pick
• concat
• append
• reverse

• reduce
• sum
• product
• mean
• join
• identity
• all
• any
• none
• find
• equals
• indexOf
• includes
• uniq

• map
• pluck
• merge
• assoc
• slice
• head
• tail
• first
• last
• take
• drop
• takeLast
• dropLast

• bind
• tap
• once
• delay
• pickBy
• pipe
• partial
• curry

• median
• groupBy
• throttle
• memoize
• shuffle
• zip
• flatten
• intersection
• difference
• split
• equals (challenge)
• indexOf (challenge)
• includes (challenge)