public string Execute()
{
MemoryStream stream = new MemoryStream();
ExecutionState state = new ExecutionState(stream);
try
{
instruction.Execute(state);
stream.Seek(0, SeekOrigin.Begin);
using (StreamReader reader = new StreamReader(stream))
return reader.ReadToEnd();
}
catch (InstructionExecutionException ex)
{
return GetErrorHTML(ex.Message, ex.Token);
}
}
public bool Execute(ExecutionState state)
{
foreach (IInstruction instruction in list)
if (!instruction.Execute(state))
return false;
return true;
}
public bool Execute(ExecutionState state)
{
string text = expression.Evaluate(state).ToString();
state.Output.Write(text);
return true;
}
protected override object Evaluate(IExpression left, IExpression right, ExecutionState state)
{
object b = right.Evaluate(state);
object a = left.Evaluate(state);
decimal x, y;
if (a is decimal)
x = (decimal)a;
else
{
TypeConverter tc = TypeDescriptor.GetConverter(a);
if (!tc.CanConvertTo(typeof(decimal)))
return string.Concat(a, b);
x = (decimal)tc.ConvertTo(a, typeof(decimal));
}
if (b is decimal)
y = (decimal)b;
else
{
TypeConverter tc = TypeDescriptor.GetConverter(b);
if (!tc.CanConvertTo(typeof(decimal)))
return string.Concat(a, b);
y = (decimal)tc.ConvertTo(b, typeof(decimal));
}
return x + y;
}
public object Evaluate(ExecutionState state)
{
return value;
}
public object Evaluate(ExecutionState state)
{
return text;
}
protected override object Evaluate(IExpression left, IExpression right, ExecutionState state)
{
object b = right.Evaluate(state);
object a = left.Evaluate(state);
return !(a.Equals(b) || b.Equals(a)); // we check both sides in case one side has overridden the Equals method
}
public object Evaluate(ExecutionState state)
{
return new NotValue(expression.Evaluate(state));
}
protected override object Evaluate(IExpression left, IExpression right, ExecutionState state)
{
object b = right.Evaluate(state);
object a = left.Evaluate(state);
decimal x, y;
if (a is decimal)
x = (decimal)a;
else
{
TypeConverter tc = TypeDescriptor.GetConverter(a);
if (!tc.CanConvertTo(typeof(decimal)))
ThrowException();
x = (decimal)tc.ConvertTo(a, typeof(decimal));
}
if (b is decimal)
y = (decimal)b;
else
{
TypeConverter tc = TypeDescriptor.GetConverter(b);
if (!tc.CanConvertTo(typeof(decimal)))
ThrowException();
y = (decimal)tc.ConvertTo(b, typeof(decimal));
}
if (y == 0)
throw new InstructionExecutionException("I can't divide the first number by the second because the second is zero. i.e. Noone can divide by zero. Not even me.", token);
return x / y;
}
public object Evaluate(ExecutionState state)
{
if(expr != null)
o = expr.Evaluate(state);
return new SoftBoolean(!(o.Equals(0m) || o.Equals(null) || o.Equals("") || o.Equals(false)));
}
protected abstract object Evaluate(IExpression left, IExpression right, ExecutionState state);
public object Evaluate(ExecutionState state)
{
return Evaluate(left, right, state);
}
protected override object Evaluate(IExpression left, IExpression right, ExecutionState state)
{
if (!(left is BooleanExpression))
left = new BooleanExpression(left);
if (!(right is BooleanExpression))
right = new BooleanExpression(right);
return left.Evaluate(state).Equals(true) && right.Evaluate(state).Equals(true);
}