static BooleanEngineBuilder() { var OperatorNode = Deferred <OperatorNode>(); var AndOperator = Terms.Text("AND") .Or( Terms.Text("&&") ); var NotOperator = Terms.Text("NOT") .Or( Terms.Text("!") ); var OrTextOperators = Terms.Text("OR") .Or( Terms.Text("||") ); // Operators that need to be NOT next when the default OR ' ' operator is found. var NotOrOperators = OneOf(AndOperator, NotOperator, OrTextOperators); // Default operator. var OrOperator = Literals.WhiteSpace() .Then <string>(static x => " ") // Normalize whitespace.