Exercise 1: Increment all the numbers in the vector [4 7 9 10] by one.
Use the map function. Hint: the function inc.
(map (fn [x] (inc x)) [4 7 9 10])
# or using the shorter form to define an anonymous function:
(map |(inc $) [4 7 9 10])
# or simply:
(map inc [4 7 9 10])
Exercise 2: Do the same as in the previous exercise, but leave only the even results in the vector.
Use the functions filter and even?
(filter even? (map inc [4 7 9 10]))
Exercise 3: Use the for structure to go through this vector of maps
and return a sequence of the :values, aka this [10.3 20.06 30.1]
[{:id 1 :value 10.3} {:id 2 :value 20.06} {:id 7 :value 30.1}]
(def data [{:id 1 :value 10.3} {:id 2 :value 20.06} {:id 7 :value 30.1}])
(for [m :in data]
(m :value))
Exercise 4: Use the function update-in to change 3 into 4 in the value below:
{:shops [:shop-1]
:customers [{:id "Bob"
:account {:balance 3}}]}
(def data {:shops [:shop-1]
:customers [{:id "Bob"
:account {:balance 3}}]})
(update-in data [:customers 0 :account :balance] inc)
Exercise 5: Create a function that combine a vector of maps like this:
(combine [{:a 1 :b 2} {:c 3} {:d 4 :e 5}])
==> {:a 1 :b 2 :c 3 :d 4 :e 5}
(defn combine [maps]
(apply merge maps))