macro
boot.janet on line 242 , column 1
(cond & pairs )
Evaluates conditions sequentially until the first true condition is
found , and then executes the corresponding body. If there are an
odd number of forms , and no forms are matched , the last expression
is executed. If there are no matches , returns nil.
(defn test
[x ]
(cond
( x 10 ) "Pretty big!"
( x 5 ) "Quite small"
"Medium size" ))
(test 40 ) # => "Pretty big!"
(test 2 ) # => "Quite small"
(test 6 ) # => "Medium size"