Macros and guiserver?

[oofoe]

Hi!

I am experimenting with macros to do more "declarative" setups in guiserver. Here is a macro that I have created to make a three button setup:

Code: Select all

(define-macro (button3 _parent _name _buttons)
  (letn ((panel (sym (string (eval _parent) "-" (eval _name))))
  	  (slots '("west" "center" "east"))
  	  (bname nil)
  	  (i nil))
  	 (gs:panel panel)
  	 (gs:set-border-layout panel)
  	 (dotimes (i (length (eval _buttons)))
  	   (setq bname (sym (string panel "-" ((eval _buttons) i 0))))
	   (println "Setting up " bname)
  	   (gs:button bname 'gs:no-action ((eval _buttons) i 1))
  	   (gs:add-to panel bname (slots i))
  	   )))

I call it like this:

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  (button3 'DC 'East  '((Next "-->") (View "<o>") (Kill "X")))

This creates a panel (DC-East) that has three buttons (DC-East-Next, DC-East-View and DC-East-Kill). They're all set up and ready to go.

However, I can't figure out how to pass in an optional event handler for each button and have the macro assemble it correctly for the gs:button call. I want to do something like this

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  ;; The "View" button doesn't have a handler yet, should default to gs:no-action.
  (button3 'DC 'East  '((Next "-->" 'next-card) (View "<o>") (Kill "X" 'kill-card)))

I am just getting invalid function or macro expansion problems when I try to do this. Any suggestions?

Thanks!

[oofoe]

OK, think I've got it. Here's the revised macro:

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(define-macro (button3 _parent _name _buttons)
  (letn ((panel (sym (string (eval _parent) "-" (eval _name))))
  	  (slots '("west" "center" "east"))
  	  (bname nil)
  	  (i nil))
  	 (gs:panel panel)
  	 (gs:set-border-layout panel)
  	 (dotimes (i (length (eval _buttons)))
  	   (setq bname (sym (string panel "-" ((eval _buttons) i 0))))
  	   (gs:button bname
		      (if (= 3 (length ((eval _buttons) i)))
			  ((eval _buttons) i 2)
			  'gs:no-action)
		      ((eval _buttons) i 1))
  	   (gs:add-to panel bname (slots i))
  	   ))
  )

The key is that the guiserver will accept strings instead of symbols, but you have to indicate the namespace (context):

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  (button3 'DC 'West 
		       '((New   "new..."   "MAIN:card-new")
		        (Clone "clone...")
		        (Back  "<--"      "MAIN:card-back")))

This will set 'card-new and 'card-back as event handlers, but the clone button will use the default gs:no-action.

It would be nice to know how to do this with proper symbols in the macro, but this is working for now and the macro simplifies my GUI setup code quite a lot.

If anyone has any improvements to suggest, I'm all ears!

[rickyboy]

Hey oofoe,

Try with a function (instead of macro); see if it works too. Here:

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(define (button3-fn _parent _name _buttons)
  (let (panel (sym (string _parent "-" _name))
        slots '("west" "center" "east"))
    (gs:panel panel)
    (gs:set-border-layout panel)
    (dolist (b _buttons)
      (let (bname (sym (string panel "-" (b 0))))
        (gs:button bname
                   (if (= 3 (length b))
                       (b 2)
                       'gs:no-action)
                   (b 1))
        (gs:add-to panel bname (slots $idx))))))

This is untested; so please test.

Also, I don't know anything about gs, so I can't comment on the rest. (I tried to get gs running on my obsd box but it seems to hang on gs:init call -- doesn't come back from the call.)

[rickyboy]

This is untested; so please test.

Also, I don't know anything about gs, so I can't comment on the rest.

I unknowingly busted a rhyme. Good Lord. :D

[oofoe]

Thanks for taking a look!

Macros are supposed to be useful for "writing the code that you would have written if you had the patience". Since guiserver uses symbols, I figured that they would be perfect for button assembly boilerplate. However, I had to cheat with sending strings to guiserver because the symbols weren't getting quoted in the correct namespace. So here I admit there's no real advantage to the macro.

It seems there's also the (macro) function, which may do more what I want. So I'll probably try it later.