Progress..

datetime.c

@@ -0,0 +1,5 @@
+#include "epoch.h"
+
+int32_t dateTimeGetYear(DateTime *dt) {
+    return dt->year.year;
+}

zone.c

@@ -31,3 +31,17 @@ void printTz(TimeZone *zone) {
         printf("%.2u:%.2u", zone->offset->hours, zone->offset->minutes);
     }
 }
+
+int64_t timezoneAsSeconds(TimeZone *tz) {
+    int64_t base;
+    
+    switch (tz->tag) {
+    case Offset:
+        base = (int64_t)tz->offset->hours * SECONDS_PER_HOUR + (int64_t)tz->offset->minutes * 60;
+        switch (tz->offset->sign) {
+        case Negative: return -base;
+        default: return base;
+        }
+    default: return 0;
+    }
+}