ipldutil

type ContextCancelError struct{}

type TraversalBuilder struct {
	Root       ipld.Link
	Selector   ipld.Node
	Visitor    traversal.AdvVisitFn
	LinkSystem ipld.LinkSystem
	Chooser    traversal.LinkTargetNodePrototypeChooser
}

type Traverser interface {
	// IsComplete returns the completion state (boolean) and if so, the final error result from IPLD
	IsComplete() (bool, error)
	// Current request returns the current link waiting to be loaded
	CurrentRequest() (ipld.Link, ipld.LinkContext)
	// Advance advances the traversal successfully by supplying the given reader as the result of the next IPLD load
	Advance(reader io.Reader) error
	// Error errors the traversal by returning the given error as the result of the next IPLD load
	Error(err error)
	// Shutdown cancels the traversal
	Shutdown(ctx context.Context)
	// NBlocksTraversed returns the number of blocks successfully traversed
	NBlocksTraversed() int
}