public bool Process(IExpressionWalker walker)
{
//result = ExpressionParser.ExternalLookup(VariableName);
result = walker.ParserVariables.Get(VariableName);
walker.ValueStack.Push(result);
return(true);
}
public bool Process(IExpressionWalker walker)
{
if (walker.ValueStack.Count == 0)
{
walker.Fail("Internal parsing error: Expected value on the left.");
return(false);
}
var left = walker.ValueStack.Pop();
if (!walker.Step() || walker.ValueStack.Count == 0)
{
if (walker.HasFailed)
{
return(false);
}
walker.Fail("Internal parsing error: Expected value on the right.");
return(false);
}
var right = walker.ValueStack.Pop();
return(process(walker, left, right));
}
protected override bool process(IExpressionWalker walker, VauleExpression right)
{
var stringValue = right as VauleExpression.StringVauleExpression;
if (stringValue == null)
{
return(walker.Fail("Internal parsing error: Expected value for run command to be a string."));
}
return(true);
}
public override bool Process(IExpressionWalker walker)
{
if (walker.ValueStack.Count == 0)
{
walker.Message("");
}
else
{
walker.Message(walker.ValueStack.Pop().Value.ToString());
}
return(true);
}
protected override bool process(IExpressionWalker walker, VauleExpression left, VauleExpression right)
{
var leftNumber = left as VauleExpression.NumericVauleExpression;
if (leftNumber == null)
{
walker.Fail("Internal parsing error: Expected value on the left to be a number.");
return(false);
}
var rightNumber = right as VauleExpression.NumericVauleExpression;
if (rightNumber == null)
{
walker.Fail("Internal parsing error: Expected value on the right to be a number.");
return(false);
}
result = new VauleExpression.FloatVauleExpression(leftNumber.Value * rightNumber.Value);
walker.ValueStack.Push(result);
return(true);
}
public abstract bool Process(IExpressionWalker walker);
protected abstract bool process(IExpressionWalker walker, VauleExpression right);
