| Program | ::= | module Id ; Block Id . |
| Block | ::= | DeclList begin StmtList end |
| DeclList | ::= | { Decl ; } |
| Decl | ::= | ConstDecl | VarDecl | ProcDecl |
| ConstDecl | ::= | const ConstDeclItem { , ConstDeclItem } |
| ConstDeclItem | ::= | Id : Type = ConstExpr |
| ConstExpr | ::= | Id | Integer |
| VarDecl | ::= | var VarDeclItem { , VarDeclItem } |
| VarDeclItem | ::= | Id : Type |
| ProcDecl | ::= | procedure Id ( [ FormalDecl {, FormalDecl }] ) ; Block Id |
| FormalDecl | ::= | Id : Type |
| Type | ::= | int |
| StmtList | ::= | { Stmt ; } |
| Stmt | ::= | CallStmt | AssignStmt | OutStmt | IfStmt | WhileStmt |
| CallStmt | ::= | Id ( [ Exprs ] ) |
| AssignStmt | ::= | LValue := Expr |
| LValue | ::= | Id |
| OutStmt | ::= | output := Expr |
| IfStmt | ::= | if Test then StmtList end |
| WhileStmt | ::= | while Test do StmtList end |
| Test | ::= | odd Sum | Sum Relop Sum |
| Relop | ::= | < | <= | = | >= | > | <> |
| Exprs | ::= | Expr { , Expr } |
| Expr | ::= | Sum |
| Sum | ::= | Term { (+ | -) Term } |
| Term | ::= | Factor { (* | /) Factor } |
| Factor | ::= | - Factor | LValue | Integer | input | ( Expr ) |
* This includes some syntactic sugar that is not strictly BNF, e.g. braces {} mean "0 or more", and brackets [] mean "optional". |
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