Language Grammar

G = (N,T,P,S)
T = [...]
N = {
    Program,
	Statement,

	Import,
	Variable
	Function,
	If,
	While,
	Class,
	Return,
	Annotation,
    Expression,

    Formals,
    Formal,
    BaseType,
    SimpleType,
    OptionType,
    Datatype,
    Block,
    ElseIf,
    Else,
    Expression_primary,
    Literal,
    Array,
    None,
    [...]
}
S = Program
P = {
	Program = { Statement } .
	Statement = ( Import | Variable | Function | If | While | Class | Return | Annotation | Expression ) ";" .

	Import = "using" (TOKEN_WORD | TOKEN_STRING) .
	Variable = "let" [ "mut" ] TOKEN_WORD "=" Expression .

	Function = "func" TOKEN_WORD Formals ( ( "->" Datatype Block ) | Block ) .
	Formals = "(" [ formal { "," formal } ] ")" .
	Formal = [ "mut" ] TOKEN_WORD ":" Datatype .

    BaseType = "int" | "char" | "bool" | "float" | "generic" | "str" | "void" | TOKEN_WORD .
    SimpleType = BaseType { "[]" } .
    OptionType = "option" TOKEN_LESS ( SimpleType | OptionType ) TOKEN_GREATER .
    Datatype = SimpleType | OptionType .

	Block = "{" { Statement } "}" .

	If = "if" Expression Block { ElseIf } [ Else ] .
	ElseIf = "else" "if" Expression Block .
	Else = "else" Block .

	While = "while" Expression Block .
	Class = "type" TOKEN_WORD Formals Block .

	Return = "return" [ Expression ] .
	Annotation = "@" ( "Getter" | "Setter" | "Unused" ) .

	Expression = Expression_primary { Operator, Expression_primary } .
	Expression_primary = Literal | TOKEN_WORD | ( "(" Expression ")" ) | Unary
                    | Call | Subscript | Subscript_sugar .


    SimpleLiteral = Float | Integer | String | Boolean | None .
	Literal = SimpleLiteral | Array .
	Array = "[", ( ( Expression { "," Expression } ) | ( "::" Datatype ) ) "]" .
    None = "None" TOKEN_LESS Datatype TOKEN_GREATER .

    Call = Expression "(" [ Expression { "," Expression } ] ")" .
    Subscript = Expression "[" Expression "]" .
    Subscript_sugar = Expression "." Ident .
}