See ChangeLog entry 19990526-13:30 EST David G. Holm <dholm@jsd-llc.com>

harbour/ChangeLog

@@ -1,3 +1,9 @@
+19990526-13:30 EST David G. Holm <dholm@jsd-llc.com>
+  * source/rtl/dates.c
+    - Added hb_dow and HARBOUR DOW() supplied by Jose Lalin <dezac@corevia.com>
+  + tests/working/dates3.prg
+    - New file to test DOW() supplied by Jose Lalin <dezac@corevia.com>
+
 19990526-17:25 Eddie Runia
   * tests/working/strip.prg
     delete broken one and moved working one in

harbour/source/rtl/dates.c

@@ -11,6 +11,11 @@
    #define _OPTIMIZE_DTOS
 #endif
 
+/*
+ADJ is 7 for ISO, 6 for no ISO
+*/
+#define ADJ 7
+
 extern STACK stack;
 
 long hb_dateEncode( long lDay, long lMonth, long lYear )
@@ -448,3 +453,36 @@ oTime->tm_mday);
       _errRelease(pError);
    }
 }
+long hb_dow( long d, long m, long y )
+{
+
+   if( m < 3 )
+      {
+         m += 13;
+         y--;
+      }
+   else
+      m++;
+
+   return ( d + 26 * m / 10 + y + y / 4 - y / 100 + y / 400 + ADJ ) % 7;
+}
+
+HARBOUR DOW( void )
+{
+   PITEM pDate = _param( 1, IT_DATE );
+   long lDay, lMonth, lYear;
+
+   if( pDate )
+   {
+      hb_dateDecode( pDate->value.lDate, &lDay, &lMonth, &lYear );
+      _retnl( hb_dow( lDay, lMonth, lYear ) );
+      stack.Return.wLength = 3;
+   }
+   else
+   {
+      PITEM pError = _errNew();
+      _errPutDescription(pError, "Error BASE/1115  Argument error: DOW");
+      _errLaunch(pError);
+      _errRelease(pError);
+   }
+}

harbour/tests/working/dates3.prg

@@ -0,0 +1,39 @@
+// Testing Harbour dates management.
+
+#include "set.ch"
+
+function main()
+
+   LOCAL dDate
+
+   set( _SET_DATEFORMAT, "dd/mm/yyyy" )
+   dDate := cToD( "25/05/1999" )
+
+   OutStd( dDate, dow( dDate ), chr( 10 ) )
+
+   OutStd( LastMonday( dDate ), chr( 10 ) )
+
+   dDate += 3
+   OutStd( dDate, dow( dDate ), chr( 10 ) )
+
+   dDate += 4
+   OutStd( dDate, dow( dDate ), chr( 10 ) )
+
+   set( _SET_DATEFORMAT, "mm/dd/yyyy" )
+   dDate := cToD( "05/25/1999" )
+
+   OutStd( dDate, dow( dDate ), chr( 10 ) )
+
+   OutStd( LastMonday( dDate ), chr( 10 ) )
+
+   dDate += 3
+   OutStd( dDate, dow( dDate ), chr( 10 ) )
+
+   dDate += 4
+   OutStd( dDate, dow( dDate ), chr( 10 ) )
+
+return nil
+
+// Like NG's sample
+function LastMonday( dDate )
+return dDate - dow( dDate ) + 2