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exercism fetch lfe strain

Strain

Implement the keep and discard operation on collections. Given a collection and a predicate on the collection's elements, keep returns a new collection containing those elements where the predicate is true, while discard returns a new collection containing those elements where the predicate is false.

For example, given the collection of numbers:

And the predicate:

Then your keep operation should produce:

While your discard operation should produce:

Note that the union of keep and discard is all the elements.

The functions may be called keep and discard, or they may need different names in order to not clash with existing functions or concepts in your language.

Restrictions

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


For installation and learning resources, refer to the exercism help page.

To run the provided tests, you will need make. Open a terminal window and run the following from the exercise directory:

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make test

You should now be able to see the results of the test suite for the exercise.

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.