tools/spec: make main an actual function

This reduces variable shadowing across the rest of the file

tools/spec.py

@@ -45,7 +45,7 @@ class Registry:
         required = []
 
         for (_, f) in self.features.items():
-            required += f.apply(reg)
+            required += f.apply(self)
             required.append(f.name)
 
         for e in self.extensions:
@@ -84,7 +84,7 @@ class Type(object):
     def declare(self):
         return ""
 
-    def define(self,reg):
+    def define(self, reg: Registry):
         return ""
 
 
@@ -695,7 +695,7 @@ def parse_commands(reg: Registry, root):
 def parse_feature(reg: Registry, root):
     assert root.tag == 'feature'
 
-    name = node.attrib['name']
+    name = root.attrib['name']
     assert name not in reg.features
 
     reg.features[name] = Feature(root)
@@ -714,7 +714,7 @@ def parse_extensions(reg: Registry, root):
 
 
 ###############################################################################
-def write_header(path: str, q: List[Type]):
+def write_header(path: str, q: List[Type], reg: Registry):
     with open(path, 'w') as dst:
         dst.write("#pragma once\n")
 
@@ -766,7 +766,7 @@ def write_header(path: str, q: List[Type]):
 
 
 ##-----------------------------------------------------------------------------
-def write_icd(path: str, q: List[Type]):
+def write_icd(path: str, q: List[Type], reg: Registry):
     with open(path, 'w') as icd:
         commands = [i for i in q if isinstance(i, Command)]
         instance_commands = [i for i in commands if i.is_instance(reg)]
@@ -813,7 +813,7 @@ def write_icd(path: str, q: List[Type]):
 
 
 ##-----------------------------------------------------------------------------
-def write_dispatch(path: str, q: List[Type]):
+def write_dispatch(path: str, q: List[Type], reg: Registry):
     with open(path, 'w') as dispatch:
         dispatch.write("""
         #include "../vk.hpp"
@@ -884,7 +884,7 @@ import argparse
 
 
 ##-----------------------------------------------------------------------------
-if __name__ == '__main__':
+def main():
     logging.getLogger().setLevel(logging.WARNING)
 
     parser = argparse.ArgumentParser(description='Transform XML API specification into C++ headers')
@@ -935,6 +935,10 @@ if __name__ == '__main__':
     q = reg.serialise(args.platform)
 
     # Finally write out the header, icd, and dispatch code.
-    write_header(args.dst, q)
-    write_icd(args.icd, q)
-    write_dispatch(args.dispatch, q)
+    write_header(args.dst, q, reg)
+    write_icd(args.icd, q, reg)
+    write_dispatch(args.dispatch, q, reg)
+
+##-----------------------------------------------------------------------------
+if __name__ == '__main__':
+    main()