Adding time-parse method.

* lib.c (time_parse_s): New symbol variable.
(tm_to_time_struct): New static function,
based on code moved out of broken_time_struct.
(broken_time_struct): Bulk of code replaced with call to
tm_to_time_struct.
(time_struct_to_tm): New parameter, strict. Indicates
whether nils in time struct are converted to zeros,
or whether they trigger errors.
(time_string_meth): Specify strict conversion
of argument time struct to to struct tm when
calling time_struct_to_tm.
(time_parse_meth): New static function.
(time_init): Initialize time_parse_s symbol variable;
add time-parse static slot to time struct;
initialize slot with new method.

* txr.1: Document time-parse method.

1 files changed, 51 insertions, 0 deletions

diff --git a/txr.1 b/txr.1
index ee4c986c..a59ec312 100644
--- a/txr.1
+++ b/txr.1
@@ -36601,6 +36601,57 @@ argument is a string, and follows exactly the same conventions as
 the format string of the C library function
 .codn strftime .
 
+.coNP Method @ time-parse
+.synb
+.mets << time-struct .(time-parse < format << string )
+.syne
+.desc
+The
+.code time-parse
+method scans a time description in
+.meta string
+according to the specification given in the
+.meta format
+string.
+
+If the scan is successful, the structure
+is updated with the parsed information, and
+the remaining unmatched portion of
+.meta string
+is returned. If all of
+.meta string
+is matched, then an empty string is returned.
+Slots of
+.meta time-struct
+which are originally
+.code nil
+are replaced with zero, even if these
+zero values are not actually parsed from
+.metn string .
+
+If the scan is unsuccessful, then
+.code nil
+is returned and the structure is not
+altered.
+
+The
+.meta format
+argument follows the same conventions as the POSIX
+C library function
+.codn strptime .
+
+Note: the
+.code time-parse
+method may be unavailable if the host system does not
+provide the
+.code strptime
+function. In this case, the
+.code time-parse
+static slot of the
+.code time
+struct is
+.codn nil .
+
 .coNP Functions @ make-time and @ make-time-utc
 .synb
 .mets (make-time < year < month < day < hour < minute < second << dst-advice )