Defun
defun is a macro in the Lisp family of programming languages that defines a function in the global environment that uses the form:
Defining the function addnumbers that adds two numbers:
;; Define a function that adds two numbers together:
)
9
Defining function square that squares a number:
;; Define a function that squares a number:
)
16
Defining a function that returns the factorial of a number:
"calculates the factorial"
1
))
720
