Re: free()

Richard Heathfield wrote:

Chris Dollin said:

<snip>

When goats are given additional pointer members (such as arms),
freeing a goat will have to deal with this. I find it easiest
to have a goatFree function right from the start, so that
I don't have to go free(aGoat)-hunting and change it.

Yes, likewise, which is why I write the destructor in the way I showed
you.

It might not only be goats that use trollguns, and anyway there may
be other circumstances where you need to destroy a trollgun other
than the one where you are destroying - sorry! deleting - a goat.

Yes - but the same argument applies: either I'm going to destroy
the place that pointed to the gun, so no point nulling it, or I'm
going to give it a new value, so no point nulling it.

No, there's another possibility - that the entity that had the gun no
longer has a gun (I dunno, perhaps the troll rips out the arm that was
holding it or something), and thus NULL is an appropriate value for
that pointer.

Yes - sometimes the new value is null.

Sometimes, rather than nulling the pointer because you're freeing it
(well, the pointed-to object), you're freeing the pointer (ditto)
because you're nulling it [1].

For me, this is often the case, (not that I use trollguns
very often) - objects gain and lose other objects with careful abandon.

Indeed.

[1] And you know this is the only surviving usable reference.

--
Chris "electric hedgehog" Dollin
"People are part of the design. It's dangerous to forget that." /Star Cops/

.

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