On 3/13/07, David Mathog <[EMAIL PROTECTED]> wrote:
...
if(i==1){}
else if(i==2){}
etc.
Hopefully things have improved since then. It is possible to force a
sort of computed goto in C (transfer control staying
within a function) but it involves pre-storing addresses of labels in
an array and then transferring control via a pointer retrieved
via an index into that array. It's too hideous to contemplate,
...
It may be too hideous to contemplate, but it's not too hideous to do, if you
want to micromanage efficiency in the proverbial innermost loop. I was just
looking at a friend's code that trades looping for indexing into an array;
it's not real pretty, grubby string munging. (It may be available as a mini
Sourceforge project, soon, but I think it will end up in an existing
package; "memrspn")
I've just made up a toy example that I've attached.
Peter
#include <stdio.h>
#define NFUNCS 2
int add1(int n);
int add2(int n);
int main(int argc, char **argv)
{
//printf("The entry point of \"printf\" is %0x\n", printf);
char c;
int (*funcTab[NFUNCS])(int);
funcTab[0] = (add1);
funcTab[1] = (add2);
printf("Would you like to add 1 or 2? (1, 2, q, Q): ");
c = getchar();
putchar(getchar());
if(c < '1' || c > '2')
{
printf("Exiting.\n");
return 0;
}
printf("The value of 10 incremented is %d\n", ((funcTab[c-'1'])(10)));
return 0;
}
int add1(int n)
{
return n+1;
}
int add2(int n)
{
return n+2;
}_______________________________________________
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