Re: hunt_victim()

From: Pink Floyd (
Date: 08/16/95

   I don't know why prototypes are required; I don't pretend to understand 
   the language at all ;>.  However, I know what has worked for me.  I do 
   not specify parameters myself; defines like ACMD and SPECIAL do it 
   already, however when I'm specifying a function directly, 'gcc' doesn't 
   care if I specify parameters or not; if I do, they have to be in the 
   right order, and if not, there's no problem.. it just assumes what the 
   previous declaration was.

Prototyping a function allows the compiler to check that you did not make
a mistake when calling any particular function.  For example, 

struct char_data *foo(struct obj_data *object, int mode)

By including this prototype (and many functions are prototyped in .h files
 so they can easily be called anywhere in the program by just including the
 header file) the compiler will be able to check, at compile time, that 
every call to the function foo() is done properly. This means not only that
the correct number of arguments is passed, and the correct type, but also
that the value returned by the function is passed to the correct type of
variable.  In my example, you must assign the outcome of foo to a pointer 
to a char_data structure.  Disabling prototypes or ignoring errors from them
is a bad idea, it entirely defeats the purpose.  
I think, but I'm not positive, that prototyping can even detect errors in the
functions themselves. (I know this kind of error is detected, and I can only
assume its a result of prototyping). If a function is declared to return a
certain type and the function (through a mistake of the coder) is able to 
terminate without returning a value, it will generate an error "control 
returned by a non-void function" or something.
Basically, prototypes are one more way of reducing human error without any
cost (i think) in the performance of the program. Use them...
BTW, ACMD() and SPECIAL() are just macros for prototyping commands and
special procedures. Look up their definition (structs.h has SPECIAL, just
grep for ACMD) and you'll see that it simply takes your ACMD argument and
turns in into a prototype for the function. Very handy. On a side note, I
learned this the hard way, that in SPECIAL, one argument is declared as 
'void *me'. In a prototype this means that any type could be passed for this
argument, and you must cast it into the type you desire.

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