protected override void SetInternal(string key, ParameterValue value)
{
_values[key] = value;
}
public override void Visit(Switch sw, State state)
{
var val = sw.Evaluator.GetValue(state.Context);
if (val.Value == null)
{
if (sw.NullExpression != null)
{
sw.NullExpression.Accept(this, state);
}
}
else
{
//Enumeration
var enumeration = val.Value as IEnumerable;
if (enumeration != null && !(enumeration is string)) //We don't want to enumerate the chars in a string
{
var vals = enumeration.Cast <object>().ToArray();
int iBackwards = -vals.Length;
for (int i = 0; i < vals.Length; i++)
{
state.Values.PushLayer();
//The parameter '#Index' provides the current index (1-indexed)
state.Values["#Index"] = ParameterValue.Wrap(i + 1);
//The parameter '#' here provides the enumerable's current value
var pval = vals[i] as ParameterValue;
if (pval == null)
{
//If the item of the enumerable is not a parameter value a clone is created to preserve wrapping, default format etc.
pval = val.Clone();
pval.Value = vals[i];
}
else
{
pval = ParameterValue.Wrap(vals[i]);
}
pval.DefaultFormat = pval.DefaultFormat ?? val.DefaultFormat;
if (sw.Formatter != null)
{
state.Values["#"] = new UnencodedParameterValue(GetParameterValue(pval, sw.Formatter, state));
}
else
{
state.Values["#"] = pval;
}
foreach (var sc in sw.Cases)
{
if (sc.Evaluator.Evaluate(ParameterValue.Wrap(i), state.Context) || sc.Evaluator.Evaluate(ParameterValue.Wrap(iBackwards), state.Context))
{
sc.Expression.Accept(this, state);
break;
}
}
state.Values.PopLayer();
++iBackwards;
}
}
else
{
//The parameter '#' is shorthand for 'evaluated value' in switches. If a format is specified for the switch parameter this is applied
state.Values.PushLayer();
state.Values["#"] = sw.Formatter != null ?
new UnencodedParameterValue(GetParameterValue(val, sw.Formatter, state)) :
val;
foreach (var sc in sw.Cases)
{
if (sc.Evaluator.Evaluate(val, state.Context))
{
sc.Expression.Accept(this, state);
break;
}
}
state.Values.PopLayer();
}
}
//Dont' visit cases individually. They are all handled in this method: base.Visit(sw, state);
}
protected abstract void SetInternal(string key, ParameterValue value);
protected override void SetInternal(string key, ParameterValue value)
{
_layers[_layers.Count - 1][key] = value;
}