public TagAttribute(string name, Expression expression)
{
this.name = name;
this.expression = expression;
}
protected object EvalExpression(Expression exp)
{
currentExpression = exp;
if (exp is StringLiteral)
return ((StringLiteral)exp).Content;
else if (exp is Name)
{
object obj = variables[((Name)exp).Id];
return obj;
}
else if (exp is FieldAccess)
{
FieldAccess fa = (FieldAccess)exp;
object obj = variables[fa.Exp];
string propertyName = fa.Field;
return EvalProperty(obj, propertyName);
}
else if (exp is IntLiteral)
return ((IntLiteral)exp).Value;
else if (exp is FCall)
{
FCall fcall = (FCall)exp;
if (!functions.ContainsKey(fcall.Name))
{
string msg = string.Format("Function {0} is not defined", fcall.Name);
WriteError(msg, exp.Line, exp.Col);
return null;
}
TemplateFunction func = functions[fcall.Name];
object[] values = new object[fcall.Args.Length];
for (int i = 0; i < values.Length; i++)
values[i] = EvalExpression(fcall.Args[i]);
return func(values);
}
else if (exp is StringExpression)
{
StringExpression stringExp = (StringExpression)exp;
StringBuilder sb = new StringBuilder();
foreach (Expression ex in stringExp.Expressions)
sb.Append(EvalExpression(ex));
return sb.ToString();
}
return null;
}
protected void ProcessExpression(Expression exp)
{
object value = EvalExpression(exp);
WriteValue(value);
}
public void Add(Expression exp)
{
exps.Add(exp);
}
public TagIf(int line, int col, Expression test)
:base(line, col, "if")
{
this.test = test;
}
public FCall(int line, int col, string name, Expression[] args)
:base(line, col)
{
this.name = name;
this.args = args;
}
