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exercism fetch elm accumulate

Accumulate

Implement the accumulate operation, which, given a collection and an operation to perform on each element of the collection, returns a new collection containing the result of applying that operation to each element of the input collection.

Given the collection of numbers:

And the operation:

Your code should be able to produce the collection of squares:

Check out the test suite to see the expected function signature.

Restrictions

Keep your hands off that collect/map/fmap/whatchamacallit functionality provided by your standard library! Solve this one yourself using other basic tools instead.

Lisp specific: it's perfectly fine to use MAPCAR or the equivalent, as this is idiomatic Lisp, not a library function.

Elm Installation

Refer to the Exercism help page for Elm installation and learning resources.

Writing the Code

The first time you start an exercise, you'll need to ensure you have the appropriate dependencies installed.

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$ npm install

Execute the tests with:

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$ npm test

Automatically run tests again when you save changes:

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$ npm run watch

As you work your way through the test suite, be sure to remove the skip <| calls from each test until you get them all passing!

Source

Conversation with James Edward Gray II https://twitter.com/jeg2

Submitting Incomplete Solutions

It's possible to submit an incomplete solution so you can see how others have completed the exercise.