Add Sten Vercammen's pattern matching library (ported to Python 3, numpy dependency replaced by standard library)

pattern_matching/enum.py

@@ -0,0 +1,31 @@
+# coding: utf-8
+
+"""
+Author:		Sten Vercamman
+			Univeristy of Antwerp
+
+Example code for paper: Efficient model transformations for novices
+url: http://msdl.cs.mcgill.ca/people/hv/teaching/MSBDesign/projects/Sten.Vercammen
+
+The main goal of this code is to give an overview, and an understandable
+implementation, of known techniques for pattern matching and solving the
+sub-graph homomorphism problem. The presented techniques do not include
+performance adaptations/optimizations. It is not optimized to be efficient
+but rather for the ease of understanding the workings of the algorithms.
+The paper does list some possible extensions/optimizations.
+
+It is intended as a guideline, even for novices, and provides an in-depth look
+at the workings behind various techniques for efficient pattern matching.
+"""
+
+class Enum(object):
+	"""
+	Custom Enum object for compatibility (enum is introduced in python 3.4)
+	Usage create	: a = Enum(['e0', 'e1', ...])
+	Usage call		: a.e0
+	"""
+	def __init__(self, args):
+		next	= 0
+		for arg in args:
+			self.__dict__[arg] = next
+			next	+= 1