add pypeg2 example

peg-parse.py

@@ -0,0 +1,26 @@
+#!/usr/bin/python3
+# https://fdik.org/pyPEG/
+
+from __future__ import division, print_function
+from pypeg2 import *
+
+class Type(Keyword):
+    grammar = Enum( K("int"), K("long") )
+class Parameter:
+    grammar = attr("typing", Type), name()
+class Parameters(Namespace):
+    grammar = optional(csl(Parameter))
+class Instruction(str):
+    grammar = word, ";"
+
+block = "{", maybe_some(Instruction), "}"
+class Function(List):
+   grammar = attr("typing", Type), name(), \
+             "(", attr("parms", Parameters), ")", block
+
+f = parse("int f(int a, long b) { do_this; do_that; }", Function)
+print(f.name)
+print(f.typing)
+print(f.parms["b"].typing)
+print(f[0])
+print(f[1])