private static LiquidExpressionResult Convert <TDest>(LiquidHash liquidHash)
where TDest : ILiquidValue
{
var destType = typeof(TDest);
// So, according to https://github.com/Shopify/liquid/wiki/Liquid-for-Designers, a hash value will be iterated
// as an array with two indices.
if (destType == typeof(LiquidCollection))
{
var newArray = new LiquidCollection();
var dictarray = liquidHash.Keys.Select(
k => (Option <ILiquidValue>) new Some <ILiquidValue>(new LiquidCollection {
LiquidString.Create(k),
liquidHash[k]
})).ToList();
foreach (var item in dictarray)
{
newArray.Add(item);
}
return(LiquidExpressionResult.Success(newArray));
}
// TODO: Should this return the default value for whatever TDest is requested?
return(LiquidExpressionResult.Error("Can't convert from a LiquidHash to " + destType));
}
private static bool CheckIsEmpty(LiquidCollection val)
{
return(!val.Any());
}
private LiquidExpressionResult DoLookup(ITemplateContext ctx, LiquidCollection liquidCollection, ILiquidValue indexProperty)
{
bool errorOnEmpty = ctx.Options.ErrorWhenValueMissing && liquidCollection.Count == 0;
String propertyNameString = ValueCaster.RenderAsString(indexProperty);
int index;
if (propertyNameString.ToLower().Equals("first"))
{
if (errorOnEmpty)
{
return(LiquidExpressionResult.Error("cannot dereference empty array"));
}
index = 0;
}
else if (propertyNameString.ToLower().Equals("last"))
{
if (errorOnEmpty)
{
return(LiquidExpressionResult.Error("cannot dereference empty array"));
}
index = liquidCollection.Count - 1;
}
else if (propertyNameString.ToLower().Equals("size"))
{
return(LiquidExpressionResult.Success(LiquidNumeric.Create(liquidCollection.Count)));
}
else
{
var success = Int32.TryParse(propertyNameString, out index);
//var maybeIndexResult = ValueCaster.Cast<ILiquidValue, LiquidNumeric>(indexProperty);
if (!success)
{
if (ctx.Options.ErrorWhenValueMissing)
{
return(LiquidExpressionResult.Error("invalid index: '" + propertyNameString + "'"));
}
else
{
return(LiquidExpressionResult.Success(new None <ILiquidValue>()));// liquid seems to return nothing when non-int index.
}
}
// if (maybeIndexResult.IsError || !maybeIndexResult.SuccessResult.HasValue)
// {
// return LiquidExpressionResult.Error("invalid array index: " + propertyNameString);
// }
// else
// {
// index = maybeIndexResult.SuccessValue<LiquidNumeric>().IntValue;
// }
}
if (liquidCollection.Count == 0)
{
return(errorOnEmpty ?
LiquidExpressionResult.Error("cannot dereference empty array") :
LiquidExpressionResult.Success(new None <ILiquidValue>()));
}
var result = liquidCollection.ValueAt(index);
return(LiquidExpressionResult.Success(result));
}