#100DaysOfClojure (Day [12] flow-control-cont)

There are a few more flow control concepts that we need to cover.

The cond function allows a series of tests and expressions with each test evaluated in order and the first true expression returned.  A small additional details in the example is the let function which binds a name to a value. Lets look at an example:

(let [x 7]

  (cond

    (< x 3) "x is less than 3"

    (< x 7) "x is less than 7"

    (< x 10) "x is less than 10"

    (< x 20) "x is less than 20"))

=> "x is less than 10"

You can even add an else statement in the event of no true expressions

(let [x 7]

  (cond

    (< x 3) "x is less than 3"

    (< x 7) "x is less than 7"

    :else "x is greater than or equal to 7"))

=> "x is greater than or equal to 7"

Then there are case expressions which are implemented as follows

( let [x 7]

  (case x

    7 (println "x is 7")

    10 (println "x is 10")

    (println "x is neither 7 nor 10")))

x is 7

=> nil

Tomorrow I will look at iterations and recursion.

(println “Bye 4 Now!”)