(empty? coll)
Returns true if coll has no items - same as (not (seq coll)). Please use the idiom (seq x) rather than (not (empty? x))
user=> (empty? ())
true
user=> (empty? '(1))
false
user=> (every? empty? ["" [] () '() {} #{} nil])
true
;example of recommended idiom for testing if not empty
user=> (every? seq ["1" [1] '(1) {:1 1} #{1}])
true
user=> (drop-while empty? ["" [] "foobar"])
("foobar")
user=> (empty? nil)
true
;; A collection with nothing in it is not empty.
(= true
(every? false? [(empty? [nil])
(empty? #{nil})
(empty? '(nil))]))
;; But a collection of nothing is empty.
(= true
(every? true? [(empty? [])
(empty? #{})
(empty? '())]))