Grammar :

program → statement* EOF ;

declaration → funDecl | varDecl| classDecl | statement ;

varDecl → "var" IDENTIFIER ( "=" expression )? ";" ;

classDecl → "class" IDENTIFIER "{" function* "}" ;

funDecl → "fun" function ;

function → IDENTIFIER "(" parameters? ")" block ;

parameters → IDENTIFIER ( "," IDENTIFIER )* ;

statement → exprStmt| forStmt | printStmt| | returnStmt | whileStmt | block ;

exprStmt → expression ";" ;

forStmt → "for" "(" ( varDecl | exprStmt | ";" ) expression? ";" expression? ")" statement ;

printStmt → "print" expression ";" ;

ifStmt → "if" "(" expression ")" statement ( "else" statement )? ;

whileStmt → "while" "(" expression ")" statement ;

block → "{" declaration* "}" ;

returnStmt → "return" expression? ";" ;

expression → assignment ;

assignment → ( call "." )? IDENTIFIER "=" assignment | logic_or ;

logic_or → logic_and ( "or" logic_and )* ;

logic_and → ternary ( "and" ternary )* ;

ternary → equality (equality (?) equality (:) equality)* ;

equality → comparison ( ( "!=" | "==" ) comparison )* ;

comparison → term ( ( ">" | ">=" | "<" | "<=" ) term )* ;

term → factor ( ( "-" | "+" ) factor )* ;

factor → unary ( ( "/" | "" ) unary ) ;

unary → ( "!" | "-" ) unary | call ;

call → primary ( "(" arguments? ")" | "." IDENTIFIER )* ;

primary → NUMBER | STRING | "true" | "false" | "nil" | "(" expression ")";

arguments → expression ( "," expression )* ;

Operator || Associativity

Equality == != Left \

Comparison > >= < <= Left\

Term - + Left\

Factor / * Left\

Unary ! - Right

Generate AST command : java src/main/java/com/interpreter/tools/GenerateAst.java "src/main/java/com/interpreter/pry/"