Use @property instead of __getattribute__ to implement lazy Package.iuse.regex

initialization.

svn path=/main/trunk/; revision=13696

diff --git a/pym/_emerge/Package.py b/pym/_emerge/Package.py
index 1b8a90c8b4d69acce78a396681f716c6e1890a80..1d90975c74aa5a65dcf020b23c88e28d3580baff 100644 (file)
--- a/pym/_emerge/Package.py
+++ b/pym/_emerge/Package.py
@@ -72,7 +72,9 @@ class Package(Task):
 
        class _iuse(object):
 
-               __slots__ = ("__weakref__", "all", "enabled", "disabled", "iuse_implicit", "regex", "tokens")
+               __slots__ = ("__weakref__", "all", "enabled", "disabled",
+                       "iuse_implicit", "tokens") + \
+                       ('_regex',)
 
                def __init__(self, tokens, iuse_implicit):
                        self.tokens = tuple(tokens)
@@ -92,20 +94,23 @@ class Package(Task):
                        self.disabled = frozenset(disabled)
                        self.all = frozenset(chain(enabled, disabled, other))
 
-               def __getattribute__(self, name):
-                       if name == "regex":
-                               try:
-                                       return object.__getattribute__(self, "regex")
-                               except AttributeError:
-                                       all = object.__getattribute__(self, "all")
-                                       iuse_implicit = object.__getattribute__(self, "iuse_implicit")
-                                       # Escape anything except ".*" which is supposed
-                                       # to pass through from _get_implicit_iuse()
-                                       regex = (re.escape(x) for x in chain(all, iuse_implicit))
-                                       regex = "^(%s)$" % "|".join(regex)
-                                       regex = regex.replace("\\.\\*", ".*")
-                                       self.regex = re.compile(regex)
-                       return object.__getattribute__(self, name)
+               @property
+               def regex(self):
+                       """
+                       @returns: A regular expression that matches valid USE values which
+                               may be specified in USE dependencies.
+                       """
+                       try:
+                               return self._regex
+                       except AttributeError:
+                               # Escape anything except ".*" which is supposed
+                               # to pass through from _get_implicit_iuse()
+                               regex = (re.escape(x) for x in \
+                                       chain(self.all, self.iuse_implicit))
+                               regex = "^(%s)$" % "|".join(regex)
+                               regex = re.compile(regex.replace("\\.\\*", ".*"))
+                               self._regex = regex
+                               return regex
 
        def _get_hash_key(self):
                hash_key = getattr(self, "_hash_key", None)