Uncaught TypeError: Cannot read property 'substring' of undefined - Processing.js - processing.js

Question

I keep getting this error, and I have no clue what is wrong. I checked all variables, but all of them are defined at least somewhere
int creatures = 5;
int deathChance = 5;
int repChance = 10;
int timer = 0;
int rand = 0;
int CurrentCreatures = 0;
int b = 0;
void draw(); {
if(timer < 100)
{
b = 0;
CurrentCreatures = creatures;
while(b < CurrentCreatures)
{
rand = random(0,100);
if(rand <= repChance)
{
creatures += 1;
}
rand = random(0,100);
if(rand <= deathChance)
{
creatures -= 1;
}
b += 1;
}
println(creatures);
timer += 1;
}
}
what the program should be doing is printing the value of creatures over 100 generations (yes this is my attempt at some "life" simulator.

Answer 1

I think the problem lies here: void Draw(); { the ; is an end of instruction character
So it is trying to execute a function called draw, the it tries to do everything inside the {'s
possibly something like:
function draw() {
if(timer < 100) {
b = 0;
CurrentCreatures = creatures;
while(b < CurrentCreatures) {
rand = random(0,100);
if(rand <= repChance) {
creatures += 1;
}
rand = random(0,100);
if(rand <= deathChance) {
creatures -= 1;
}
b += 1;
}
println(creatures);
timer +=1;
}
}