Clojure Programming/Examples/API Examples/do Macros
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doseq
[edit | edit source](doseq [i [1 2 3 4]] (print i))
; This is an example of using destructuring to pair an index with each element of a seq.
(doseq [[index word] (map vector
(iterate inc 0)
["one" "two" "three"])]
(prn (str index " " word)))
doall
[edit | edit source]user=> (doall (map #(println "hi" %) ["mum" "dad" "sister"]))
hi mum hi dad hi sister (nil nil nil)
dorun
[edit | edit source]user=> (dorun (map #(println "hi" %) ["mum" "dad" "sister"]))
hi mum hi dad hi sister nil
doto
[edit | edit source](doto (new java.util.HashMap) (.put "a" 1) (.put "b" 2))
-> {a=1, b=2}
NB: doto returns the object after modification, which is very convenient. Consider in the above example no variable binding is required to access the resultant object.
(.addChild *scene-graph*
(doto (KeyNavigatorBehavior.
(-> *universe* .getViewingPlatform .getViewPlatformTransform))
(setSchedulingBounds (BoundingSphere. (Point3d.) 10000.0))))
Here you can see it is much more readable using doto than the alternative which would be to create a temporary binding with let.