new example

git-svn-id: https://swig.svn.sourceforge.net/svnroot/swig/trunk/SWIG@791 626c5289-ae23-0410-ae9c-e8d60b6d4f22

Examples/python/reference/example.py

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+# file: example.py
+
+# This file illustrates the manipulation of C++ references in Python
+# This uses the low-level interface.  Shadow classes work differently.
+
+import example
+
+# ----- Object creation -----
+
+print "Creating some objects:"
+a = example.new_Vector(3,4,5)
+b = example.new_Vector(10,11,12)
+
+print "    Created",example.Vector_print(a)
+print "    Created",example.Vector_print(b)
+
+# ----- Call an overloaded operator -----
+
+# This calls the wrapper we placed around
+#
+#      operator+(const Vector &a, const Vector &) 
+#
+# It returns a new allocated object.
+
+print "Adding a+b"
+c = example.addv(a,b)
+print "    a+b =", example.Vector_print(c)
+
+# Note: Unless we free the result, a memory leak will occur
+example.delete_Vector(c)
+
+# ----- Create a vector array -----
+
+# Note: Using the high-level interface here
+print "Creating an array of vectors"
+va = example.new_VectorArray(10)
+print "    va = ",va
+
+# ----- Set some values in the array -----
+
+# These operators copy the value of $a and $b to the vector array
+example.VectorArray_set(va,0,a)
+example.VectorArray_set(va,1,b)
+
+# This will work, but it will cause a memory leak!
+
+example.VectorArray_set(va,2,example.addv(a,b))
+
+# The non-leaky way to do it
+
+c = example.addv(a,b)
+example.VectorArray_set(va,3,c)
+example.delete_Vector(c)
+
+# Get some values from the array
+
+print "Getting some array values"
+for i in range(0,5):
+    print "    va(%d) = %s" % (i, example.Vector_print(example.VectorArray_get(va,i)))
+
+# Watch under resource meter to check on this
+print "Making sure we don't leak memory."
+for i in xrange(0,1000000):
+    c = example.VectorArray_get(va,i % 10)
+
+# ----- Clean up -----
+print "Cleaning up"
+
+example.delete_VectorArray(va)
+example.delete_Vector(a)
+example.delete_Vector(b)
+