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    Imperative Loops (for & while) in Reason


    In functional programming languages map, filter and reduce are often preferred over imperative loops. As stated in the official Reason docs the language creates don't have a preference on whether you should use a loop over these function.

    In Reason we have for as well as while available.



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    Instructor: We can use for loops to iterate from the starting value up to the ending value. The ending value is included.

    Keep in mind, though, it must be a valid range going from a lower to a higher integer. Otherwise, it won't go through any of these items. In order to make the loop count in the opposite direction, we can replace to with down-to.

    In addition, we have while loops at our disposal. They loop as long as the test condition inside the parentheses is true.