program -> scope

statement -> assignment
statement -> if statement
statement -> while statement
statement -> break
statement -> return
statement -> put output
statement -> get input
statement -> scope
statement -> procedure call

expression -> integer
expression -> true
expression -> false
expression -> - expression
expression -> expression + expression
expression -> expression - expression
expression -> expression * expression
expression -> expression / expression
expression -> expression ^ expression
expression -> ! expression
expression -> expression & expression
expression -> expression | expression
expression -> expression = expression
expression -> expression != expression
expression -> expression < expression
expression -> expression <= expression
expression -> expression > expression
expression -> expression >= expression
expression -> ( expression )
expression -> variable
expression -> function call

output -> expression
output -> text
output -> newline

input -> variable

declaration -> type : identifier
declaration -> type : identifier = expression
declaration -> const type : identifier = expression
declaration -> type : identifier [ expression ]
declaration -> type function identifier ( parameters ) scope
declaration -> procedure identifier ( parameters ) scope

type -> integer
type -> boolean

argument -> expression

parameter -> type : identifier
parameter -> type : identifier []
parameter -> var type : identifier

variable -> identifier
variable -> identifier [ expression ]

function call -> identifier (arguments)

procedure call -> identifier (arguments)