Map laziness in clojure

Question

I am creating a simple swing GUI in Clojure. I am trying to apply a single function to several GUI components using a map in a let context:

(map #(f % component4) [component1 component2 component3])

Where all components are defined in let.

Problemically, the card is lazy, and the action does not apply to the components, however I can force it by wrapping the above in "take".

Is there an alternative card for lazy cards? Or should I go about it differently?

EDIT: Use counterclockwise in an eclipse. I had different results using (use "Lib: reload") from REPL and using CTRL + Enter from the editor. Rebooting launches the GUI, but the problem described above will occur. The problem did not occur when using CTRL + Enter from the editor, so I think my description of the problem may be inaccurate. Regardless of the fact that the dose is the best alternative map in this scenario.

Answer 1

I dispute your claim that the involvement of take has any meaning. If you wrapped it in doall or dorun , it will do what you want, but you should use doseq instead of map for this kind of action for side effects only.

Note

Originally posted as a comment on the question; copied to answer by popular request.

Answer 2

doseq is probably the best way to approach this. the dose is roughly equivalent to the “for everyone” instruction, which crosses each element of the collection in many other languages. It is guaranteed that he will not be lazy.

 (doseq [comp [component1 component2 component3]] (f comp component4)) 

Some general recommendations:

• Use the card and its lazy friends (including pick, delete, etc.) when you want the sequence to be the result
• Use dose , doall , dotimes , etc. when you are more interested in side effects.

Answer 3

Wrapping your card in doall will make it appreciate. or a better alternative is the dose that is used for things related to side effects.