Compare returns -1, 0, or 1 if a is less than, equal to, or greater than b.

NewMinMap constructs an empty MinMap.

A MinMap provides a mapping of keys to Stamp values, while also tracking the minimum value.

Queue maintains ordered Stamped values.

Coalescing is an optional interface that may be implemented by Stamped values.

A Stamp is a comparable value (possibly a time, or an offset within a log file).

A Stamped value has some key by which it can be ordered.