Methods in time struct: time-local and time-utc.

* lib.c (time_local_s, time_utc_s): New symbol variables.
(time_meth): New static function.
(time_init): Initialize new symbol variables. Create the
time struct with two static slots, and initialize those
static slots to be methods.

* txr.1: Introduce "the epoch" term. Document the
new methods.

1 files changed, 38 insertions, 1 deletions

diff --git a/txr.1 b/txr.1
index f5d4214d..a70d1623 100644
--- a/txr.1
+++ b/txr.1
@@ -35159,7 +35159,9 @@ pseudo-random number generator.
 The
 .code time
 function returns the number of seconds that have elapsed since
-midnight, January 1, 1970, in the UTC timezone.
+midnight, January 1, 1970, in the UTC timezone: a point in
+time called
+.IR "the epoch" .
 
 The
 .code time-usec
@@ -35302,6 +35304,41 @@ function or from the
 .code time-usec
 function.
 
+.coNP Methods @ time-local and @ time-utc
+.synb
+.mets << time-struct .(time-local)
+.mets << time-struct .(time-utc)
+.syne
+.desc
+The
+.code time
+structure has two methods called
+.code time-local
+and
+.codn time-utc .
+
+The
+.code time-local
+function considers the slots of the
+.code time
+structure instance
+.meta time-struct
+to be local time, and returns its integer representation
+as the number of seconds since the epoch.
+
+The
+.code time-utc
+function is similar, except it considers
+the slots of
+.meta time-struct
+to be in the UTC time zone.
+
+Note: these functions work by converting the slots into arguments
+which are applied to
+.code make-time
+or
+.codn make-time-utc .
+
 .coNP Functions @ make-time and @ make-time-utc
 .synb
 .mets (make-time < year < month < day < hour < minute < second << dst-advice )