Re: AST observations
Jeremy Hylton <[email protected]> Thu, 18 Apr 2002 14:53:48 -0400
| Newsgroups | gmane.comp.python.compiler |
|---|---|
| Message-ID | <[email protected]> |
Finally, I should say that I don't have any strong attachment to the visitor code in the compiler package. Nor do I have any strong attachment to the AST it defines. I've started over with python.asdl, and I don't have any problems with starting over on a new visitor structure. Let's find the ideas that work best for all our applications. I'm probably going to want something visitor like implemented in C for the builtin bytecode compiler; I don't have any idea what that will look like yet. Efficiency was a non-goal for compiler.visitor. I didn't even consider whether generating efficient Java code was possible. (What would be the point of writing in the subset of Python that can be translated efficiently to Java? <wink>) We're kindof stuck with compiler package as it exists now, since it's a std part of 2.2. But there's no reason it can't grow new classes that provide new or improved functionality. On the subject of what the right visitor style is, it looks like Eelco and Joost Visser are doing interesting work in this area on the guide pattern and visitor combinators, respectively. (I don't have any idea of the people are related, although the ideas are at some level :-). I don't have links handy, but I a google search on name + visitor will get you there. Eric-- Feel free to contribute concrete patches that make the existing visitor code faster. I tried to speed it up too, once, and didn't make much progress. Much as you saw, I didn't see obvious changes that made a big difference. Jeremy