// TODO: this is inefficient and ugly and duplicates much of LiquidCollection
private LiquidExpressionResult DoLookup(ITemplateContext ctx, LiquidString str, ILiquidValue indexProperty)
{
var strValues = str.StringVal.ToCharArray().Select(ch => LiquidString.Create(ch.ToString()).ToOption()).ToList();
String propertyNameString = ValueCaster.RenderAsString(indexProperty);
int index;
if (propertyNameString.ToLower().Equals("first"))
{
index = 0;
}
else if (propertyNameString.ToLower().Equals("last"))
{
index = strValues.Count - 1;
}
else if (propertyNameString.ToLower().Equals("size"))
{
return(LiquidExpressionResult.Success(LiquidNumeric.Create(strValues.Count)));
}
else
{
//var maybeIndexResult = ValueCaster.Cast<ILiquidValue, LiquidNumeric>(indexProperty);
var numericIndexProperty = indexProperty as LiquidNumeric;
if (numericIndexProperty == null)
{
return(ctx.Options.ErrorWhenValueMissing ?
LiquidExpressionResult.Error("invalid string index: '" + propertyNameString + "'") :
LiquidExpressionResult.Success(new None <ILiquidValue>()));
}
else
{
index = numericIndexProperty.IntValue;
}
}
if (strValues.Count == 0)
{
//return LiquidExpressionResult.Error("Empty string: " + propertyNameString);
return(LiquidExpressionResult.Success(new None <ILiquidValue>())); // not an error in Ruby liquid.
}
return(LiquidExpressionResult.Success(CollectionIndexer.ValueAt(strValues, index)));
}
//public IList<Option<ILiquidValue>> ArrValue { get { return _values; } }
public Option <ILiquidValue> ValueAt(int key)
{
return(CollectionIndexer.ValueAt(_values, key));
}