module DeclExpr

exports
  sorts Body Stmt Decl Declarator Expr
  context-free syntax
                       -> Body
    Body Stmt          -> Body
    Decl "S"           -> Stmt
    Expr "S"           -> Stmt
    Id Declarator      -> Decl
    "A"                -> Id
    "B"                -> Id
    Id                 -> Declarator
    "L" Declarator "R" -> Declarator
    Id                 -> Expr
    Expr "L" Expr "R"  -> Expr