# HG changeset patch
# User Paul Boddie <paul@boddie.org.uk>
# Date 1512334794 -3600
# Node ID d1f864ab0a165810e1ab3ba843dd75748a86a7de
# Parent  9b6843537c2fbd0d56f838171a90973e2167512c
Introduced symbols for resolution levels and a mapping from levels to symbols.

diff -r 9b6843537c2f -r d1f864ab0a16 vRecurrence.py
--- a/vRecurrence.py	Sun Dec 03 19:50:50 2017 +0100
+++ b/vRecurrence.py	Sun Dec 03 21:59:54 2017 +0100
@@ -75,6 +75,23 @@
 
 YEARS, MONTHS, WEEKS, DAYS, HOURS, MINUTES, SECONDS = 0, 1, 2, 5, 6, 7, 8
 
+# Special levels for day frequency qualifiers.
+
+YEARDAYS, MONTHDAYS = 3, 4
+
+# Special levels used by non-qualifier-originating selectors.
+
+COUNT, DTSTART, BYSETPOS = -2, -1, None
+
+level_labels = (
+    "YEARS", "MONTHS", "WEEKS", "YEARDAYS", "MONTHDAYS", "DAYS", "HOURS",
+    "MINUTES", "SECONDS",
+
+    # Negative indexes.
+
+    "COUNT", "DTSTART"
+    )
+
 # Enumeration levels, employed by BY... qualifiers.
 
 enum_levels = (
@@ -289,10 +306,10 @@
     # Create a selector that must be updated with the maximum resolution.
 
     elif qualifier == "BYSETPOS":
-        return PositionSelector(None, args, "BYSETPOS")
+        return PositionSelector(BYSETPOS, args, "BYSETPOS")
 
     elif qualifier == "COUNT":
-        return LimitSelector(-2, args, "COUNT")
+        return LimitSelector(COUNT, args, "COUNT")
 
     else:
         return Pattern(freq[qualifier], args, qualifier)
@@ -301,7 +318,7 @@
 
     "Return a copy of 'selectors' incorporating 'dt'."
 
-    selectors = selectors + [StartSelector(-1, {"start" : dt}, "DTSTART")]
+    selectors = selectors + [StartSelector(DTSTART, {"start" : dt}, "DTSTART")]
     selectors.sort(key=selector_sort_key)
     return selectors
 
@@ -871,7 +888,8 @@
         self.first = first
 
     def __repr__(self):
-        return "%s(%r, %r, %r, %r)" % (self.__class__.__name__, self.level,
+        return "%s(%s, %r, %r, %r)" % (self.__class__.__name__,
+                                       level_labels[self.level],
                                        self.args, self.qualifier, self.first)
 
     def select(self, start, end, inclusive=False):