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We are working towards making exercises stand-alone. That is to say: no more generating READMEs on the fly. This will give maintainers more control over each individual exercise README, and it will also make some of the backend logic for delivering exercises simpler. The README template uses the Go text/template package, and the default templates generate the same READMEs as we have been generating on the fly. See the documentation in [regenerating exercise readmes][regenerate-docs] for details. The READMEs can be generated at any time using a new 'generate' command in configlet. This command has not yet landed in master or been released, but can be built from source in the generate-readmes branch on [configlet][]. [configlet]: https://github.com/exercism/configlet [regenerate-docs]: https://github.com/exercism/docs/blob/master/maintaining-a-track/regenerating-exercise-readmes.md
65 lines
1.6 KiB
Markdown
65 lines
1.6 KiB
Markdown
# Accumulate
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Implement the `accumulate` operation, which, given a collection and an
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operation to perform on each element of the collection, returns a new
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collection containing the result of applying that operation to each element of
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the input collection.
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Given the collection of numbers:
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- 1, 2, 3, 4, 5
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And the operation:
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- square a number (`x => x * x`)
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Your code should be able to produce the collection of squares:
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- 1, 4, 9, 16, 25
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Check out the test suite to see the expected function signature.
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## Restrictions
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Keep your hands off that collect/map/fmap/whatchamacallit functionality
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provided by your standard library!
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Solve this one yourself using other basic tools instead.
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Lisp specific: it's perfectly fine to use `MAPCAR` or the equivalent,
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as this is idiomatic Lisp, not a library function.
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## Elm Installation
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Refer to the [Exercism help page](http://exercism.io/languages/elm) for Elm
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installation and learning resources.
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## Writing the Code
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The first time you start an exercise, you'll need to ensure you have the
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appropriate dependencies installed.
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```bash
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$ npm install
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```
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Execute the tests with:
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```bash
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$ npm test
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```
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Automatically run tests again when you save changes:
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```bash
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$ npm run watch
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```
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As you work your way through the test suite, be sure to remove the `skip <|`
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calls from each test until you get them all passing!
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## Source
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Conversation with James Edward Gray II [https://twitter.com/jeg2](https://twitter.com/jeg2)
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## Submitting Incomplete Solutions
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It's possible to submit an incomplete solution so you can see how others have completed the exercise.
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