public override void Function()
{
switch (Operation)
{
case ArithmeticOperation.SUM:
Value = Val1 + Val2;
break;
case ArithmeticOperation.SUBTRACT:
Value = Val1 - Val2;
break;
case ArithmeticOperation.MULTIPLY:
Value = Val1 * Val2;
break;
case ArithmeticOperation.DIVIDE:
try
{
Value = Val1 / Val2;
}catch (DivideByZeroException ex)
{
DivisionByZeroException exx = new DivisionByZeroException();
exx.blox = this.NodeBlox;
throw exx;
}
break;
}
}
private Lazy <object> VisitArithmeticExpression(ParserRuleContext context, ParserRuleContext op,
ParserRuleContext left, ParserRuleContext right)
{
var expressionType = _scriptEnvironmentBuilder.TypeInferenceVisitor.Visit(context);
if (!TypeUtil.IsNumeric(expressionType) && expressionType != ObjectType.String)
{
_scriptEnvironmentBuilder.Errors.Add(
new InvalidOperandsException(
context,
op.GetText(),
_scriptEnvironmentBuilder.TypeInferenceVisitor.Visit(left),
_scriptEnvironmentBuilder.TypeInferenceVisitor.Visit(right)));
return(new Lazy <object>(() => null));
}
return(new Lazy <object>(() =>
{
var leftValue = left.Accept(this).GetValueOrLazyValue();
var rightValue = right.Accept(this).GetValueOrLazyValue();
if (op.GetText() == "+")
{
//maybe we have string concatenation?
if (leftValue is string leftStr)
{
return leftStr + rightValue;
}
if (rightValue is string rightStr)
{
return leftValue + rightStr;
}
}
if (!(leftValue is int) && !(leftValue is double) ||
!(rightValue is int) && !(rightValue is double))
{
return null;
}
bool TryConvertToNumber(object value, out double result)
{
result = 0;
try
{
result = Convert.ToDouble(value);
}
catch (InvalidCastException e)
{
Errors.Add(new FailedToInferTypeException(context, left, e));
return false;
}
return true;
}
if (!TryConvertToNumber(leftValue, out var leftValueAsNumber))
{
return null;
}
if (!TryConvertToNumber(rightValue, out var rightValueAsNumber))
{
return null;
}
switch (op.GetText())
{
case "+":
return Cast(leftValueAsNumber + rightValueAsNumber, expressionType);
case "-":
return Cast(leftValueAsNumber - rightValueAsNumber, expressionType);
case "/":
if (Math.Abs(rightValueAsNumber) < 0.00000000001) //epsilon :)
{
var error = new DivisionByZeroException(context);
Errors.Add(error);
}
var val = leftValueAsNumber / rightValueAsNumber;
return Cast(val, expressionType);
case "%":
return Cast(leftValueAsNumber % rightValueAsNumber, expressionType);
case "*":
return Cast(leftValueAsNumber * rightValueAsNumber, expressionType);
}
//if not numeric and not string concatenation, nothing to do...
return null;
}));
}
