ROOT ::= INSTR*

INSTR ::=
| LEXPR semicolon
| BEXPR

EXPR ::= LEXPR | BEXPR

LEXPR ::=
| OR
| ASSERT EXPR
| VARDECL
| CONSTDECL
| ASSIGN

BEXPR ::=
| BLOCK
| IF

IF ::=
| if EXPR BLOCK
| if EXPR BLOCK else BLOCK
| if EXPR BLOCK else IF

BLOCK ::= obrace INSTR* cbrace
VARDECL ::= var ident colon type? assign EXPR
CONSTDECL ::= ident colon type? assign EXPR
ASSIGN ::= ident assign EXPR

OR ::= AND (or AND)*
AND ::= EQNE (and EQNE)*
EQNE ::= CMP ((eq|ne) CMP)?
CMP ::= TERM ((lt|le|gt|ge) TERM)?
TERM ::= FACTOR ((add|sub) FACTOR)*
FACTOR ::= POW ((mul|div|mod) POW)*
POW ::= NOT (pow NOT)?

NOT ::= not* LITERAL
LITERAL ::= ident | BUILTIN | opar EXPR cpar
BUILTIN ::= bool | int | float | string