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Best Practice: Variables

If you're on this site at all, I'm sure you know what a variable is. They store data!

Different languages have different ways of declaring them. Here are a few examples

# you can just say that x = y and a variable will be created:
x = 10
y = "Snake!"

// both var and let declare variables that you can change
var x = 10;
let y = "Not Java"; // it's best practice to use let instead

// const declares a value that you cannot change later, hence the name
const z = 10;

// in C++, you use the variable type as the declaration
int x = 15;
bool y = true;

// dart is very similar to C++. The type is the declaration
int x = 10;
String y = "Flutter? I hardly know her!";
Array<int> z = [1, 2, 3];

However, GameMaker Language is a little different. There are 3 ways of declaring variables.

Global Variables

Of course, you can declare a global variable using the global keyword. This will make the variable available to every object after it has been declared.

obj_game > Create
global.kills = 0
global.player_name = "Neil"
global.ammo = 60
obj_player > Step
if global.ammo > 0 {
    shoot_enemy() // pretend this does something...
}

Note

It's best to declare global variables at the start of your game. Such as in the Create event of an object that it spawned first thing. This avoids potential issues if you try to call a global variable before it has been assigned.