Variables

Syntax

int x = 7;
string y;
var str = "foo";

The variable is set to a default value if there is no initializer. Objects with a constructor must have an initializer.

The var keyword can be used to inference the type of the variable using the initializer.

Scopes

Variable obey the traditional rules of scoping, so variables can be redefined inside of scopes and can be accessed from descendent scopes.

int x = 7;
int y = 3;

{
    // Valid, x is now a long in this scope
    long x = 2;
    print(y);
}

Casting

Values can attempt to be casted to other types. There are two main types of casting: implicit and explicit. Implicit casting, as the name suggests, is done automatically where applicable. Explicit casting happens when using the cast expression:

string str = "Hi";
int x = (int)str;

info

Explicit casting is mainly used for casting down an inheritance tree. However some types have special explicit casting rules. For instance, casting anything to an int will effectively use /execute store. So for most values, it will call /data get and store that into a score.

Math

All the normal operators work as expected (except % for now).

Amethyst also provides the following unary operators:

• ++x
• --x
• !x
• -x

note

Postfix increment and decrement (x++) does not exist due to clarity concerns. This may change in the future.

warning

Minecraft may handle integer division slightly differently than the languages you are used to.

Strings

Strings in Amethyst are implemented using NBT strings. Only double quotes are supported for now.

string str = "Hello World";

tip

All Minecraft string escape codes can be used.

Methods

• .length(): String length. Compiles internally as (int)str.

Lists

Lists store an ordered collection of values. Untyped lists (using list) are unsupported currently.

int[] list = [-7];

list.add(10);
list.add(5);
list.add(x * y);

print(list[2]);

Methods

• .add(T val): Add a value to the end of the list.
• .size(): Get the size of the list.

warning

There are currently no bounds checks. Eventually it will be included in debug builds and optionally in release mode builds.

Objects

Typeless NBT compounds can be created using the nbt type:

nbt x = { thing1: 7, thing2: 6s };
x.property = "Hi";
print(x);