Function Pointers in C are Underrated
vickychijwani.github.com
Function Pointers in C are Underrated
1–10 of 33 posts
Re: Function Pointers in C are Underrated
#2I don't quite understand what is meant by this. Function pointers are not "underrated"; that implies that it is lower or higher than something. Being the only way to perform an indirect branch in C, it's not really something you rate. It just is.
Re: Function Pointers in C are Underrated
#3TLDR: You can write a comparator function and use it like with C's 'qsort'.
Re: Function Pointers in C are Underrated
#4C function pointers are prime citizens for 42 years. Nobody underrates them. 'cdecl' is a fun way to learn all about them.
C++ 's inline templates beat them in performance though.
Re: Function Pointers in C are Underrated
#5I don't quite understand what is meant by this. Function pointers are not "underrated"; that implies that it is lower or higher than something. Being the only way to perform an indirect branch in C, it's not really something you rate. It just is.
I interpret the statement as being closer to "function pointers are under-discussed".
Re: Function Pointers in C are Underrated
#6This should probably be called "Function pointers in C are AWESOME". because they are. Function Pointers are basically C's implementation for callbacks too! There are some awesome things people can do with fp's, and i especially like C++'s use of function pointers and function objects with respect to the STL algorithms and the use of tr1::bind and std::not1 in the functional header. Cool Stuff!
Re: Function Pointers in C are Underrated
#7The linux kernel has a cool linked list implementation for purposes like this, which IMHO is much prettier. Essentially you put a struct list (or hlist) inside of a struct you use in a list. This struct can be a simple pointer to data, or a full struct itself. Whatever. Then the list macros and functions just work on your data structure.
Implementation details here: http://lxr.linux.no/linux+v3.3/include/linux/rculist.h (also look up list.h).
My favorite part is wrapping your head round the container_of macro central to this. ( http://lxr.linux.no/linux+v3.3/tools/perf/util/include/linux... )
Not that function pointers aren't neat or useful, but sometimes there are other cool solutions too :)
Re: Function Pointers in C are Underrated
#8Equating function pointers with closures in the second paragraph isn't a good start…
Re: Function Pointers in C are Underrated
#9I don't quite understand what is meant by this. Function pointers are not "underrated"; that implies that it is lower or higher than something. Being the only way to perform an indirect branch in C, it's not really something you rate. It just is.
Through the title, I'm just trying to point out that function pointers are not as well-known in C as in other languages. Programmers should recognize when and how to use them effectively.
Re: Function Pointers in C are Underrated
#10The author claims you might know it as a lambda or anonymous function in other languages, but I think function pointers come up short in comparison.
Function pointers can't capture variables from surrounding scopes and so can't depend on runtime values in any easy or safe way.
Just try emulating the following with function pointers:
def incrementor(n: Int) = (x:Int) => x + n