🚀 go-pugleaf

In article <1992Dec28.144429.1427@jupiter.sun.csd.unb.ca> kinsman@jupiter.sun.csd.unb.ca (Aphoriel/Kinsman) writes:
>This is a question from someone new to C...
>
>How could I set up C code so that a program goes to a function where the name
>of the function is placed in a string variable? The specific use I'm thinking
>of is for an adventure game, where the function the parser calls depends on
>the verb the player used in typing in his command.. I could set it up as:
>
>-If verb_parsed is 'eat' then call eat_function
>-If verb_parsed is 'give' then call give_function
>
>and so forth, but this is awful... How could I write it in C to look like:
>
>-Go to [verb_parsed + string_holding_parameter_characters]
>
>Like that.
>
>Thanks in advance,
>-Sean Givan / Aphoriel/Kinsman


hurm, well, perhaps the simplest way (assuming all your functions take
the same parameters) is something like this:

typedef int (*FuncPtr)();

FuncPtr arrayOfFunctions[] = {func1, func2, func3...};

/* code to set i to the proper index of the function you want */

FuncPtr f;
f = arrayOfFunctions[i];
f(/* params, if any */);

i've seen this used most commonly for programs that have a variable
function that is decided by the user (such as a program to graph y =
f(x) where the user choses f from a list).  you can use a structure,
one element of which is a string (the key for looking up the
function), the other of which is your function pointer.

note: you can cheat, and use functions that don't all take the same
paramaters, but be careful, and make sure you're passing the right
number to the function...

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