Re: Functionoids vs Pointer to Member Functions
On 18 Aug., 23:45, Immortal Nephi <Immortal_Ne...@hotmail.com> wrote:
I did read section [33] under C++ FAQs Lite. It talks about pointer
to member functions and functionoids. Someone claims that
functionoids runs faster than traditional pointer to function and
pointer to member functions, but another denies their claim. They say
functionoids can be slow because it requires high overheads through
three pointers.
It really depends on what you think a "functionoid" is and how this
thing will be used. Also, I don't think a lot of people use the term
"functionoid" which raises the question how comments about
"functionoids" got into this FAQ.
Anyway ... There are multiple examples on that page with varying
runtime/code size trade-offs. What they have in common is that it's
about invoking functions on objects as opposed to using plain function
pointers. (Note: Pointer to member functions are NOT compared to
"functionoids" on that page). One example uses an abstract base class
with a virtual "doit" member function and another uses templates with
function objects that don't have virtual member functions. It's a
completely different thing. Take your pick.
I would appreciate if someone
already tested functionoids and pointer to member functions.
They can tell which is faster.
If I am going to use functionoids instead of pointer to member
functions
What kind of "functionoids"? How would you use them? How would you use
pointers to member functions?
at compile-time, then all derived classes are unable to
share base class' data members.
Why are they unable?
[snip]
It's probably for the best if you explain the problem you are trying
to solve.
Cheers!
SG