# Functions
IsContextCancelErr checks whther the given err is ContextCancelError or has a one wrapped.
# Structs
ContextCancelError is a sentinel that indicates the passed in context was cancelled.
TraversalBuilder defines parameters for an iterative traversal.
# Interfaces
Traverser is an interface for performing a selector traversal that operates iteratively -- it stops and waits for a manual load every time a block boundary is encountered.