protected override object Evaluate(IExpression left, IExpression right, ExecutionState state)
{
object b = TokenParser.VerifyUnderlyingType(right.Evaluate(state, token));
object a = TokenParser.VerifyUnderlyingType(left.Evaluate(state, token));
decimal x, y;
if (a is decimal)
{
x = (decimal)a;
}
else
{
TypeConverter tc = TypeDescriptor.GetConverter(a);
if (!tc.CanConvertTo(typeof(decimal)))
{
ThrowException(a);
}
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(b);
}
y = (decimal)tc.ConvertTo(b, typeof(decimal));
}
return(x - y);
}
public static object EvaluateArguments(ExecutionState state, object o, List <ExpressionArgument> args, Token contextToken)
{
if (o == null)
{
if (contextToken.Previous != null)
{
throw new InstructionExecutionException("\"" + contextToken.Previous.Value + "\" is not a keyword and has not been assigned a value as a variable. As such, it cannot evaluate the specified argument list.", contextToken.Previous);
}
throw new InstructionExecutionException("The value here is null, which isn't able to process an argument list.", contextToken);
}
if (o is IList)
{
if (args.Count > 1)
{
throw new InstructionExecutionException("I can't evaluate the arguments for this list because you've specified more than one argument. The only argument you can specify for a list is a numeric expression indicating which list item you're referring to.", contextToken);
}
object n = TokenParser.VerifyUnderlyingType(args[0].Expression.Evaluate(state, args[0].Token));
if (!(n is decimal))
{
throw new InstructionExecutionException("The argument you specified doesn't equate to a number, which is required to specify which list item you're referring to.", args[0].Token);
}
int index = Convert.ToInt32(n);
if (index >= ((IList)o).Count)
{
throw new InstructionExecutionException("The index specified here is higher than the highest index in the list. Remember, the lowest index is 0 and the highest is one less than the total number of items in the list.", args[0].Token);
}
return(((IList)o)[index]);
}
throw new InstructionExecutionException("This type of object isn't able to process an argument list. (Underlying type: " + o.GetType().Name, contextToken);
}
protected override object Evaluate(IExpression left, IExpression right, ExecutionState state)
{
object b = TokenParser.VerifyUnderlyingType(right.Evaluate(state, token));
object a = TokenParser.VerifyUnderlyingType(left.Evaluate(state, token));
return(!(a.Equals(b) || b.Equals(a))); // we check both sides in case one side has overridden the Equals method
}
protected override object Evaluate(IExpression left, IExpression right, ExecutionState state)
{
object b = TokenParser.VerifyUnderlyingType(right.Evaluate(state, token));
object a = TokenParser.VerifyUnderlyingType(left.Evaluate(state, token));
if (a is IComparable && b is IComparable)
{
return(((IComparable)a).CompareTo(b) <= 0);
}
throw new InstructionExecutionException("I can't check if the first thing is less than or equal to the second thing because they're not really comparable in that way.", token);
}
public override bool Equals(object o)
{
object val = TokenParser.VerifyUnderlyingType(o);
if (val == null)
{
return(!value);
}
bool oValue = !(val.Equals(0m) || val.Equals(null) || val.Equals("") || val.Equals(false));
return(value == oValue);
}
protected override object Evaluate(IExpression left, IExpression right, ExecutionState state)
{
object b = TokenParser.VerifyUnderlyingType(right.Evaluate(state, token));
object a = TokenParser.VerifyUnderlyingType(left.Evaluate(state, token));
decimal x, y;
if (a is decimal)
{
x = (decimal)a;
}
else
{
TypeConverter tc = TypeDescriptor.GetConverter(a);
if (!tc.CanConvertTo(typeof(decimal)))
{
ThrowException(a);
}
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(b);
}
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);
}
protected override object Evaluate(IExpression left, IExpression right, ExecutionState state)
{
object b = TokenParser.VerifyUnderlyingType(TokenParser.ReduceFromExpression(state, token, right.Evaluate(state, token)));
object a = TokenParser.VerifyUnderlyingType(TokenParser.ReduceFromExpression(state, token, left.Evaluate(state, token)));
if (a == null || b == null)
{
if (a == null || b == null)
{
return(true);
}
else
{
return(false);
}
}
if ((a is decimal && b is string) || (a is string && b is decimal))
{
decimal k, m;
bool result;
if (a is decimal && b is string)
{
k = (decimal)a;
result = decimal.TryParse((string)b, out m);
}
else
{
k = (decimal)b;
result = decimal.TryParse((string)a, out m);
}
if (result)
{
return(k.Equals(m));
}
}
return(a.Equals(b) || b.Equals(a)); // we check both sides in case one side has overridden the Equals method
}
protected override object Evaluate(IExpression left, IExpression right, ExecutionState state)
{
object b = TokenParser.VerifyUnderlyingType(right.Evaluate(state, token));
object a = TokenParser.VerifyUnderlyingType(left.Evaluate(state, token));
decimal x, y;
//typeof(decimal).IsAssignableFrom(typeof(a))
if (a is decimal)
{
x = (decimal)a;
}
else
{
//if(a is int || a is long || a is double || a is float || a is short
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);
}
