tk-stack-mark

[Daniel Ridge]

Bug in ice-9/boot-9.scm:save-stack ?

I notice that save-stack references tk-stack-mark which does not  
appear to exist or to be the obvious transposition of any existing  
symbol name.

My uninformed intuition is that tk-stack-mark is brought in by some  
optional package not shipped by default with Guile (perhaps guile-tk?).

I never cause this bug, but I do check my Scheme system with a semi- 
static analysis that complains about tk-stack-mark being undefined and  
I would prefer not to special-case a rule for save-stack. Perhaps all  
interests could be served by:

...
((tk-stack)
   (apply make-stack #t save-stack (if (defined? 'tk-stack-mark) tk- 
stack-mark (stack-id #t)) #t 0 narrowing)
...

or by some cond-expand foo or by outright banishment of this case?

Thanks,
        Dan