'''Purpose: ''' [Kevin Kenny] is comtemplating starting a project to
rework the [clock] command.  The purpose of this page is to present
some of the issues with the current [[clock]] command, and collect
feedback about how best to fix it.
----
The current (Tcl 8.4a3) [[clock]] command has served us well since Tcl 7.5, but it's starting to show cracks at all levels.  It appears that nothing less than a complete rework may suffice to fix all the issues.  (In that case, the existing [[clock]] command will be preserved, but deprecated.)

'''1. The measurement of time.'''

At present, Tcl's concept of absolute time is the count of seconds from a fixed ''epoch'' or zero point.  The count is expressed as a signed 32-bit integer.  This representation has a number of drawbacks.

   * ''Range.'' The representation of time cannot represent dates before 1902 nor after 2038.  It is only a few years before banking applications, for instance, which deal with 30-year loans will run into the end of the permissible range.

   * ''Precision.'' The granularity of a second is not adequate for disambiguating timestamps in a number of applications.  Now that NTP is a near-universal part of the networking infrastructure, it is routine to keep different systems' clocks synchronized to within a few milliseconds to tens of milliseconds, and one would want to time-stamp actions