$hashfile.key[string]
Stores to disk the association between key and string.
$hashfile.key[
$.value[string]
$.expires(number of days)
]
$hashfile.key[
$.value[string]
$.expires[date]
]
Such a construction allows to specify the date for association to expire. There can be specified number of days or some specific date.
Optional modifiers:
$.expires(number of days) - specifies number of days (can have fractional part, 1.5=day and a half), during which to keep key/string pair, 0 days=forever; $.expires[$date] - specifies date and time until which the association will be kept, here $date-the variable of date type.
Note: there is a limit on key and value strings, together they must not exceed 8000 bytes.