Clojurians Log v2

Can someome review my code : https://github.com/RoelofWobben/Learning_in_public/blob/main/ground_up/src/ground_up/chapter5.clj

a small thing: :false and :true should probably be false and true - then your macro can just be (if logging-enabled (prn ~message))`

the nil is implicit, and message needs to be unquoted

in the style of your previous macro, (prn ~message)` could also be (list prn message)` the two are equivalent

@noisesmith thanks, I see now only a the message (prn message) and not (prn :hi) as the challenge said the outcome should be

and a message that the else branch is missing

wait, who says an else branch is missing?

it's optional

here

I disagree with clj-kondo, but it's clj-kondo (a style tool) telling you this

it's harmless to add a nil else branch, but it is also redundant

(ins)user=> (if false :OK)
nil
(ins)user=> (if false :OK nil)
nil

it runs so I do not have a problem with it

the only thing that worries me that I see prn message as output instead of (pnr :hi) as stated in the challenge

your original will show that:

(defmacro log [message]
  (if (= logging-enabled :true)
    `(prn message)
    nil))

(defmacro log [message]
  (if logging-enabled
   `(prn ~message)))

notice the ~ to unquote message

change the if to a when to mollify clj-kondo

or and if you think when is only for side effects and don't mind a random false instead of nil :D

@noisesmith then I see (prn ~ message) as output

are you sure you aren't using ' instead of ` ?

the ~ should not show up in the macro expand, it's a special instruction to the ` reader macro

yes, im sure

(def logging-enabled true)

(defmacro log [message]
  (if logging-enabled
    '(prn ~message)))


(macroexpand `(log :hi))

that's not `, it's '

it's the wrong one

oke, this code works

thanks for the feedback

glad I could help