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Clojure: Cond

Для самых сложных случаев, там, где обычно применяется if-else_if в Clojure есть еще одна форма: cond:

 (pos? -5) "first return"
 (zero? -5) "second return"
 (pos? 5) "third return"
 :else "boom!")

Эта форма напоминает case, только в левой части находится предикат. Если его результат истина, то выполняется правая часть и её результат возвращается из cond.
Если необходимо, в конце добавляется :else, который ведет себя аналогично else в других языках.


Реализуйте функцию programmer-level, которая принимает на вход количество баллов, и возвращает уровень разработчика на основе этого числа. Если баллов от 0 до 10, то это junior, от 10 до 20 – middle, от 20 и выше – senior.

(programmer-level 10) ; middle
(programmer-level 0) ; junior
(programmer-level 40) ; senior
The exercise doesn't pass checking. What to do? 😶

If you've reached a deadlock it's time to ask your question in the «Discussions». How ask a question correctly:

  • Be sure to attach the test output, without it it's almost impossible to figure out what went wrong, even if you show your code. It's complicated for developers to execute code in their heads, but having a mistake before their eyes most probably will be helpful.
In my environment the code works, but not here 🤨

Tests are designed so that they test the solution in different ways and against different data. Often the solution works with one kind of input data but doesn't work with others. Check the «Tests» tab to figure this out, you can find hints at the error output.

My code is different from the teacher's one 🤔

It's fine. 🙆 One task in programming can be solved in many different ways. If your code passed all tests, it complies with the task conditions.

In some rare cases, the solution may be adjusted to the tests, but this can be seen immediately.

I've read the lessons but nothing is clear 🙄

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