コード例 #1
0
ファイル: Interpreter.cs プロジェクト: lurivasm/CompilerMPL
        /**
         * Function VisitUnaryExpr
         * Param : unary expression to evaluate
         * Return : the negated value of the right operand or error
         */
        public Value VisitUnaryExpr(Expr.Unary expr)
        {
            Value right = Evaluate(expr.Right);

            /* If the operator is NOT and the right operand is BOOL */
            if (expr.OperatorToken.Kind == TokenKind.Not)
            {
                if (right.Type.Equals(VALTYPE.BOOL))
                {
                    return(new Value(VALTYPE.BOOL, !((bool)right.Val)));
                }
                /* If the right operand is not BOOL throw an error */
                else
                {
                    throw new RuntimeError(expr.OperatorToken, "Trying to negate a non bool value");
                }
            }
            return(null);
        }
コード例 #2
0
        /**
         * Function VisitUnaryExpr : checks that the operator is NOT and
         * that the right expression is BOOL. Otherwise throws an error
         * Param : unary expression to ckeck
         * Return : the type of the unary expression
         */
        public VALTYPE VisitUnaryExpr(Expr.Unary expr)
        {
            VALTYPE right = GetType(expr.Right);

            /* If the operator is NOT and the right expr is BOOL */
            if (expr.OperatorToken.Kind == TokenKind.Not)
            {
                if (right.Equals(VALTYPE.BOOL))
                {
                    return(right);
                }
                /* Error if right expr is not BOOL */
                else
                {
                    throw new TypeError(expr.OperatorToken, "'" + expr.OperatorToken.Text
                                        + "' expects a BOOL expression, got " + right.ToString() + " instead.");
                }
            }
            /* Single operand */
            else
            {
                return(right);
            }
        }
コード例 #3
0
ファイル: AstPrinter.cs プロジェクト: lurivasm/CompilerMPL
 /**
  * Function VisitUnaryExpr
  * Param : unary expression to visit
  * Return : parenthesized string of the value
  */
 public String VisitUnaryExpr(Expr.Unary expr)
 {
     return(Parenthesize(expr.OperatorToken.Text, expr.Right));
 }