Variable Localization in Sub-Routines.

[Lee Mac]

Hi Guys,

 

Sorry for the plethora of Thread I've created today, but I have a sudden influx of questions that, if answered, would fill various holes in my knowledge of LISP.

 

My question is this:

 

If I have a subroutine, say for creating a list, and I set the list to a variable say "a", do I localise this variable in the sub-routine, and, if I do, will it still be available in the main routine?

 

i.e.

 

(defun c:test ()
   (testa)
   (alert a)
   (princ)
) ;_  end defun

(defun testa (/ [b][color=Red]a[/color][/b])
   (setq a (getstring t))
) ;_  end defun

 

Should I localise the highlighted variable, and, if I do, can I still use it in the main routine as shown?

 

Also, should I also localise it in the main routine?

[ASMI]

(defun c:test2 (/ b)
 (setq b(testa))
   (alert b)
   (princ)
) ;_  end defun

 

or

 

(defun c:test3 ()
   (alert(testa))
   (princ)
) ;_  end defun

[Lee Mac]

Thanks for your help ASMI, that is a bit of a work-around, and works well.

 

After a bit of experimentation, I have found that if you have a sub-routine with some variables that are then used in the main-routine, these variables should be localised in the main-routine and not the sub-routine for them to hold their values.

 

Otherwise, their values are set to nil after the sub-routine has completed.

[ASMI]

After a bit of experimentation, I have found that if you have a sub-routine with some variables that are then used in the main-routine, these variables should be localised in the main-routine and not the sub-routine for them to hold their values.

 

Yes. Place subfunction inside main function to make it local (for LISP correctly to speak function).

 

(defun c:mainfun(/ [color="SeaGreen"][b]a[/b][/color])

 (defun subfun()
   (setq [color="SeaGreen"][b]a[/b][/color] ...)
 ); end subfun
...
(princ)
); end c:maifun

[Lee Mac]

for LISP correctly to speak function...

 

 

Haha, I've really gotta learn the LISP lingo

 

 

Thanks ASMI, help appreciated as always