Pattern Matching with core.match
Remarks#
The core.match
library implements a pattern match compilation algorithm that uses the notion of “necessity” from lazy pattern matching.
Matching Literals
(let [x true
y true
z true]
(match [x y z]
[_ false true] 1
[false true _ ] 2
[_ _ false] 3
[_ _ true] 4))
;=> 4
Matching a Vector
(let [v [1 2 3]]
(match [v]
[[1 1 1]] :a0
[[1 _ 1]] :a1
[[1 2 _]] :a2)) ;; _ is used for wildcard matching
;=> :a2
Matching a Map
(let [x {:a 1 :b 1}]
(match [x]
[{:a _ :b 2}] :a0
[{:a 1 :b _}] :a1
[{:x 3 :y _ :z 4}] :a2))
;=> :a1
Matching a literal symbol
(match [['asymbol]]
[['asymbol]] :success)
;=> :success