Fold a run of paired frames into the four numbers.
Pure: no clock, no state, no I/O. frames is a whole run — the caller keeps the window it wants and this makes no decision about how long the operator has been watching.
frames
Fold a run of paired frames into the four numbers.
Pure: no clock, no state, no I/O.
framesis a whole run — the caller keeps the window it wants and this makes no decision about how long the operator has been watching.