How to Change Python's Grammar

pep-0306.txt

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+PEP: 306
+Title: How to Change Python's Grammar
+Version: $Revision$
+Last-Modified: $Date$
+Author: Michael Hudson <mwh@python.net>
+Status: Draft
+Type: Informational
+Content-Type: text/plain
+Created: 29-Jan-2003
+Post-History:
+
+
+Abstract
+
+    There's more to changing Python's grammar than editing
+    Grammar/Grammar and Python/compile.c.  This PEP aims to be a
+    checklist of places that must also be fixed.
+
+    It is probably incomplete.  If you see omissions, just add them if
+    you can -- you are not going to offend the author's sense of
+    ownership.  Otherwise submit a bug or patch and assign it to mwh.
+
+    This PEP is not intended to be an instruction manual on Python
+    grammar hacking.
+
+
+Rationale
+
+    People are getting this wrong all the time; it took well over a
+    year before someone noticed[1] that adding the floor division
+    operator (//) broke the parser module.
+
+
+Checklist
+
+    __ Grammar/Grammar: OK, you'd probably worked this one out :)
+
+    __ Python/compile.c: you'll most likely need to edit both the
+       actual compiler and the symtable builder (which is to say both
+       the com_foo and the sym_foo functions).
+
+    __ You may need to regenerate Lib/symbol.py and/or Lib/token.py.
+
+    __ The parser module.  Add some of your new syntax to test_parser,
+       bang on parsermodule.c until it passes.
+
+    __ The compiler package.  A good test is to compile the standard
+       library and test suite with the compiler package and then check
+       it runs.  You did add some of your new syntax to the test
+       suite, didn't you?  There's a script in Tools/compiler that
+       does this.
+
+
+References
+
+    [1] SF Bug #676521, parser module validation failure
+        http://www.python.org/sf/676521
+
+
+Copyright
+
+    This document has been placed in the public domain.
+
+
+
+Local Variables:
+mode: indented-text
+indent-tabs-mode: nil
+sentence-end-double-space: t
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+End: