timeout: Return a new number after a given number of seconds
Description
This function will return a number corresponding to the system time and
remain stable until a given number of seconds have elapsed, after which it
will update to the current time. This makes it useful as a way to timeout
and invalidate a memoised cache after a certain period of time.
Usage
timeout(seconds, current = as.numeric(Sys.time()))
Arguments
seconds
Number of seconds after which to timeout.
current
The current time as a numeric.
Value
A numeric that will remain constant until the seconds have elapsed.