how can use # in let

Question

Here is sample code

(def showscp
     ( let [ cf     (seesaw.core/frame :title "cframe")]
       (do
         (seesaw.core/config! cf :content (seesaw.core/button :id :me :text "btn" ))
         (.setSize cf 300 300)
         (seesaw.core/show! cf)
         cf
       )
     )
)

For get button, I use this

(defn find-me 
   ([frame]
         (let [ btn (seesaw.core/select frame [:#me] )  ] (do btn)
         )
   )
)

It cause error, like

Syntax error reading source at (REPL:2:1). EOF while reading, starting at line 2

(I guess :#me is problem in macro.)

why error cause, and how can I avoid error.

Is there more smart way than (keyword "#me")

score 1 · Answer 1 · answered Aug 04 '20 at 22:45

# is only special at the beginning of a token, to control how that token is parsed. It's perfectly valid as part of a variable name, or a keyword. Your code breaks if I paste it into a repl, but works if I retype it by hand. This strongly suggests to me that you've accidentally included some non-printing character, or other weird variant character, into your function.

score 0 · Answer 2 · answered Aug 04 '20 at 18:51

0

You can't use #, because it is a dispatch character.

# is a special character that tells the Clojure reader (the component that takes Clojure source and "reads" it as Clojure data) how to interpret the next character

answered Aug 04 '20 at 18:51

akond

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score 0 · Answer 3 · answered Aug 04 '20 at 18:52

The pound character (aka octothorpe) is a special reader control character in Clojure, so you can't use it in a literal keyword, variable name, etc.

Your suggestion of (keyword "#me") will work, although it would probably be better to modify your code to just use the string "#me", or to eliminate the need for the pound-char altogether.

how can use # in let

3 Answers3