recap-what-does-clojure-look-like.md

What does Clojure look like?

Writing Clojure with parentheses

Parentheses ( ) are a list in Clojure and define the structure of your code.

A left parenthesis is the start of the list and needs a matching right parenthesis. If you have unmatched parentheses then Clojure will not read your code correctly and you will get an error.

Editors that support Clojure help you manage your parentheses

Calling functions

The first thing in a list is a call to a function.

Calling functions make your code do something. You usually call a function along with one or more values (referred to as arguments).

There are many built-in functions in Clojure and you can also define your own.

Here are some examples of calling functions:

(+ 3 4)

(def username "john")

(str "Hello" " " "World!")

(str "Welcome to our website: " (clojure.string/capitalize username))

+, str and def are all functions.

When these functions get run, they return a some type of value.

Clojure functions always return a value.

Function arguments

Many functions take in arguments which are everything else inside the enclosing parentheses after the function-.

(str "Hello" " " "World!")

In the above example, str takes 3 strings as arguments, "Hello", " " and "World!" and returns the string "Hello, World!" .

(+ 3 4)

+ takes 3 and 4, adds them, and returns 7.