program → declaration* EOF ;
declaration → variableDecl | statement ;
variableDecl → "var" IDENTIFIER ("=" expression)? "**;**" ;
statement → exprStmt | printStmt | block | ifStmt ;
exprStmt → expression ";" ;
printStmt → print expression ";" ;
block → "{" (declaration)* "}" ;
ifStmt → "if" "(" expression ")" statement ("else" statement)? ;
whileStmt → "while" "(" expression ")" statement ;
forStmt → "for" "(" (varDecl | exprStmt) ";" expression? ";" expression? ";" ")" ;
A comma expression evaluates to the final expression
comma expr → expression , (expression)* | "(" expression ")";
expression → comma_expression | ternary | literal | unary | binary | grouping ;
expression → ternary;
ternary → assignment | assignment ? assignment : assignment;
assignment → logic_or | IDENTIFIER "=" ternary ;
logic_or → logic_and ( "or" logic_and)* ;
logic_and → equality ("and" equality)* ;
equality → comparsion ("==" | "!=" comparison)*;
comparison → term ("<="|"<"|">"|">=" term)*;
term → factor ("+"|"-" factor)*;
factor → unary (( "%" | "/" | "*" ) unary )*;
unary → ("-" | "!") unary | primary;
primary → literal | IDENTIFIER | "(" expression ")" ;
literal → NUMBER | STRING | "true" | "false" | "nil" ;
grouping → "(" expression ")" ;
unary → ( "-" | "!" ) expression ;
binary → expression operator expression ;
operator → "==" | "!=" | "<" | "<=" | ">" | ">=" | "+" | "-" | "*" | "/" | "%"**;**