elm/exercises/accumulate/README.md

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# 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:
- 1, 2, 3, 4, 5
And the operation:
- square a number (`x => x * x`)
Your code should be able to produce the collection of squares:
- 1, 4, 9, 16, 25
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](http://exercism.io/languages/elm) 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.
```bash
$ npm install
```
Execute the tests with:
```bash
$ npm test
```
Automatically run tests again when you save changes:
```bash
$ 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](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.