private static IEnumerable <IExampleSpace <ContextualValue <TProjection, TContext> > > ContextualizedUnfoldSubspaceInternal <TAccumulator, TContext, TProjection>(
TContext context,
IEnumerable <TAccumulator> accumulators,
ContextualizedUnfoldFunctions <TAccumulator, TContext, TProjection> functions)
{
IExampleSpace <ContextualValue <TProjection, TContext> > GenerateNextExampleSpace(
TAccumulator accumulator,
TContext context0)
{
return(UnfoldInternal(accumulator, context0, functions));
}
return(TraverseUnencountered(accumulators, context, functions.NextContext, GenerateNextExampleSpace).Select(exampleSpace =>
{
var currentExample = exampleSpace.Current;
var context0 = functions.NextContext(currentExample.Value.Value, currentExample.Value.Context);
var exampleWithMoreContext = new Example <ContextualValue <TProjection, TContext> >(
currentExample.Id,
new ContextualValue <TProjection, TContext>(currentExample.Value.Value, context0),
currentExample.Distance);
return new ExampleSpace <ContextualValue <TProjection, TContext> >(
exampleWithMoreContext,
exampleSpace.Subspace);
}));
}
private static IExample <ContextualValue <TProjection, TContext> > CreateExample <TAccumulator, TContext, TProjection>(
TAccumulator accumulator,
TContext context,
ContextualizedUnfoldFunctions <TAccumulator, TContext, TProjection> functions)
{
var id = functions.Identify(accumulator);
var value = functions.Projection(accumulator);
var distance = functions.Measure(accumulator);
return(new Example <ContextualValue <TProjection, TContext> >(
id,
new ContextualValue <TProjection, TContext>(value, context),
distance));
}
public static IExampleSpace <ContextualValue <TProjection, TContext> > UnfoldInternal <TAccumulator, TContext, TProjection>(
TAccumulator accumulator,
TContext context,
ContextualizedUnfoldFunctions <TAccumulator, TContext, TProjection> functions)
{
var example = CreateExample(accumulator, context, functions);
var context0 = functions.NextContext(example.Value.Value, context);
var(context1, shrinks) = functions.Shrink(accumulator, context0);
var subspace = ContextualizedUnfoldSubspaceInternal(context1, shrinks, functions);
return(new ExampleSpace <ContextualValue <TProjection, TContext> >(example, subspace));
}
public static IExampleSpace <T> Unfold <T, TContext>(
T rootValue,
ContextualShrinker <T, TContext> contextualShrinker,
MeasureFunc <T> measure,
IdentifyFunc <T> identify)
{
var functions = new ContextualizedUnfoldFunctions <T, TContext, T>(
contextualShrinker.ContextualShrink, measure, identify, x => x, contextualShrinker.ContextualTraverse);
var contextualizedExampleSpace = UnfoldHelpers.UnfoldInternal(
rootValue,
contextualShrinker.RootContext,
functions);
return(contextualizedExampleSpace.Map(x => x.Value));
}
