🚀 go-pugleaf

Philippe Verdy <100105.3120@compuserve.com> wrote:

>Many recursive data structures require algorithms to handle
>them which have to mark and unmark all scanned objects in
>order to avoid infinite recursion when walking on that
>structure, or when building items iterator.

The property of being marked is really part of your algorithm, not
part of the object itself.  You should consider making some sort of
separate record (a list of some sort) to indicate which items are
marked and unmarked.  Otherwise, you'll then find an algorithm where
you have to mark things twice, and so on...

>Is there any way (or proposal) to explicitly specify members
>of a class definition which are relaxed on constness certi-
>fication ?

Sounds like "mutable" to me.

>And is constness definition a semantic only definition,

Being const means only that the current function won't change the
object, not that the object itself won't change during the function.
It could change as the result of a side effect of another function
called within the current one.  Thus unless only inline or other
internally known functions are called, no additional optimizations are
possible.

Andrew Bell
abell@mindspring.com
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