public override Maybe<Result> VisitBasic_expr(QueryParser.Basic_exprContext context) { if (context.ADD() != null) return VisitAdd(context); if (context.SUB() != null) return VisitSub(context); return VisitFact_expr(context.fact_expr()); }
private Maybe<Result> VisitSub(QueryParser.Basic_exprContext context) { var (left, right) = VisitTwo(context); return left.Zip(right).Bind(tuple => tuple.Item1.Subtract(tuple.Item2).Just()); }
private (Maybe<Result>, Maybe<Result>) VisitTwo(QueryParser.Basic_exprContext context) { var left = new BasicExprVisitor(_zmi, _env).Visit(context.basic_expr()); var right = new BasicExprVisitor(_zmi, _env).Visit(context.fact_expr()); return (left, right); }
/// <summary> /// Visit a parse tree produced by <see cref="QueryParser.basic_expr"/>. /// <para> /// The default implementation returns the result of calling <see cref="AbstractParseTreeVisitor{Result}.VisitChildren(IRuleNode)"/> /// on <paramref name="context"/>. /// </para> /// </summary> /// <param name="context">The parse tree.</param> /// <return>The visitor result.</return> public virtual Result VisitBasic_expr([NotNull] QueryParser.Basic_exprContext context) { return(VisitChildren(context)); }