/// <summary>
/// Marshals a boolean value into native VW.
///
/// e.g. loggedIn = true yields "loggedIn" in VW native string format.
/// e.g. loggedIn = false yields an empty string.
/// </summary>
/// <param name="context">The marshalling context.</param>
/// <param name="ns">The namespace description.</param>
/// <param name="feature">The feature description.</param>
/// <param name="value">The actual feature value.</param>
public void MarshalFeature(VowpalWabbitMarshalContext context, Namespace ns, PreHashedFeature feature, bool value)
{
Contract.Requires(context != null);
Contract.Requires(ns != null);
Contract.Requires(feature != null);
if (!value)
{
return;
}
context.NamespaceBuilder.AddFeature(feature.FeatureHash, 1f);
context.AppendStringExample(feature.Dictify, " {0}", feature.Name);
}
/// <summary>
/// Expects that actual feature value.
/// </summary>
private void ParseFeature(VowpalWabbitMarshalContext context, Namespace ns, string featureName)
{
switch (reader.TokenType)
{
case JsonToken.Float:
{
var feature = new PreHashedFeature(this.vw, ns, featureName);
this.defaultMarshaller.MarshalFeature(context, ns, feature, (double)reader.Value);
}
break;
case JsonToken.Integer:
{
var feature = new PreHashedFeature(this.vw, ns, featureName);
this.defaultMarshaller.MarshalFeature(context, ns, feature, (long)reader.Value);
}
break;
case JsonToken.String:
{
var feature = new Feature(featureName);
this.defaultMarshaller.MarshalFeatureStringEscapeAndIncludeName(context, ns, feature, (string)reader.Value);
}
break;
case JsonToken.Boolean:
{
var feature = new PreHashedFeature(this.vw, ns, featureName);
this.defaultMarshaller.MarshalFeature(context, ns, feature, (bool)reader.Value);
}
break;
case JsonToken.Comment:
case JsonToken.Null:
// probably best to ignore?
break;
case JsonToken.StartArray:
this.ParseFeatureArray(context, ns);
break;
default:
throw new VowpalWabbitJsonException(reader.Path, "Unexpected token " + reader.TokenType + " while deserializing primitive feature");
}
}
internal static void Marshal(VowpalWabbitDefaultMarshaller defaultMarshaller, VowpalWabbitMarshalContext context, Namespace ns, string featureName, long val)
{
var feature = new PreHashedFeature(context.VW, ns, featureName);
defaultMarshaller.MarshalFeature(context, ns, feature, val);
}
