linear unique_array lifted from saviour, lifted from a python cookbook.

svn path=/main/trunk/; revision=2488

diff --git a/pym/portage_util.py b/pym/portage_util.py
index 2441509d9d8ebb2cad652a7c92c8ea6b9b4be259..f45f46b600b6cfc601babe863353df9027bd3116 100644 (file)
--- a/pym/portage_util.py
+++ b/pym/portage_util.py
@@ -392,15 +392,6 @@ def pickle_read(filename,default=None,debug=0):
                data = default
        return data
 
-def unique_array(array):
-       """Takes an array and makes sure each element is unique."""
-       mya = []
-       for x in array:
-               if x not in mya:
-                       mya.append(x)
-       return mya
-
-
 def dump_traceback(msg, noiselevel=1):
        import sys, traceback
        info = sys.exc_info()
@@ -417,3 +408,37 @@ def dump_traceback(msg, noiselevel=1):
        if error:
                writemsg(error+"\n", noiselevel=noiselevel)
        writemsg("====================================\n\n", noiselevel=noiselevel)
+
+def unique_array(s):
+       """lifted from python cookbook, credit: Tim Peters
+       Return a list of the elements in s in arbitrary order, sans duplicates"""
+       n = len(s)
+       # assume all elements are hashable, if so, it's linear
+       try:
+               return list(set(s))
+       except TypeError:
+               pass
+
+       # so much for linear.  abuse sort.
+       try:
+               t = sorted(s)
+       except TypeError:
+               pass
+       else:
+               assert n > 0
+               last = t[0]
+               lasti = i = 1
+               while i < n:
+                       if t[i] != last:
+                               t[lasti] = last = t[i]
+                               lasti += 1
+                       i += 1
+               return t[:lasti]
+
+       # blah.  back to original portage.unique_array
+       u = []
+       for x in s:
+               if x not in u:
+                       u.append(x)
+       return u
+