Variables

Declaration/Assignment

There are two ways to declare a variable:

1. Declare using a top-level `var` statement.

var variable_name = const_expr;

2. Declare by assigning a value to the variable.

The first assignment to a variable is considered its declaration.

variable_name = value;

type_name variable_name = value;

Variables for all sprites

If a variable is assigned to in `stage.gs`, it will be declared as **for all sprites**.

Variables for this sprite only

Variables are by-default declared as **for this sprite only**. If you want to declare a variable **for all sprites**, assign to it in `stage.gs`.

Local Variables

Local variables are accessible only within the procedure they are declared in.

The first assignment with the `local` keyword will declare a local variable, all further uses of the variable will refer to the local variable. If a normal variable with the same name exists, it will be shadowed.

proc my_procedure {
    local x = 0;
    x = x + 1;
}

In the compiled Scratch project, the variable `x` will be named as `my_procedure:x`.

!!! note Local variables will have undefined behavior if the procedure is recursive, or is NOT a run-without-screen-refresh procedure.

Compound Assignment

+------------+---------------------------------------------------------+
|  Operator  |                     Implementation                      |
+============+=========================================================+
| `x++;`     | 
=> ../assets/increment.png [IMG]
{width="150"}           |
+------------+---------------------------------------------------------+
| `x--;`     | 
=> ../assets/decrement.png [IMG]
{width="150"}           |
+------------+---------------------------------------------------------+
| `x += y;`  | 
=> ../assets/assign_add.png [IMG]
{width="150"}          |
+------------+---------------------------------------------------------+
| `x -= y;`  | 
=> ../assets/assign_subtract.png [IMG]
{width="150"}     |
+------------+---------------------------------------------------------+
| `x *= y;`  | 
=> ../assets/assign_multiply.png [IMG]
{width="150"}     |
+------------+---------------------------------------------------------+
| `x /= y;`  | 
=> ../assets/assign_divide.png [IMG]
{width="150"}       |
+------------+---------------------------------------------------------+
| `x //= y;` | 
=> ../assets/assign_floor_divide.png                    |
|            | [IMG]
{width="150"}                                      |
+------------+---------------------------------------------------------+
| `x %= y;`  | 
=> ../assets/assign_mod.png [IMG]
{width="150"}          |
+------------+---------------------------------------------------------+
| `x &= y;`  | 
=> ../assets/assign_join.png [IMG]
{width="150"}         |
+------------+---------------------------------------------------------+

Show/Hide Variable Monitor

show variable_name;

hide variable_name;