Read version in setup.py

Author: grantjenks

setup.py

@@ -1,10 +1,24 @@
 from setuptools import setup, Extension
+import re
+
+def get_version():
+    """
+    Extract the version number from arraydeque.c.
+    Looks for a line of the form:
+        #define ARRAYDEQUE_VERSION "0.1.0"
+    """
+    with open("arraydeque.c", "r", encoding="utf-8") as f:
+        content = f.read()
+    match = re.search(r'#define\s+ARRAYDEQUE_VERSION\s+"([^"]+)"', content)
+    if match:
+        return match.group(1)
+    raise RuntimeError("Unable to find version string in arraydeque.c.")
 
 module = Extension('arraydeque', sources=['arraydeque.c'])
 
 setup(
     name='arraydeque',
-    version='0.1',
+    version=get_version(),
     description='Array-backed deque implementation',
     ext_modules=[module],
 )