Import a module without executing it?

Kent Johnson kent3737 at yahoo.com
Wed Dec 8 05:44:52 EST 2004


Andy, this is a nice example. It prompted me to look at the docs for compiler.visitor. The docs are, 
um, pretty bad. I'm going to attempt to clean them up a little. Would you mind if I include this 
example?

Thanks,
Kent

Andy Gross wrote:
> Here's a quick example that will pull out all functions defined in the 
> top-level of a module:
> 
> ---
> #/usr/bin/env python
> from compiler import parse, walk
> from compiler.visitor import ASTVisitor
> 
> testdata = r'''
> def aFunction(anArg):
>     return anArg + 1
> '''
> class SimpleVisitor(ASTVisitor):
>     def visitFunction(self, parsedFunc):
>         print "Function %(name)s at %(lineno)s takes %(argnames)s " \
>               " with code %(code)s" % parsedFunc.__dict__
> 
> if __name__ == "__main__":
>     ast = parse(testdata)
>     walk(ast, SimpleVisitor(), verbose=True)
> ---
> 
> andy at alyosha:~$ ./test.py
> Function aFunction at 2 takes ['anArg']  with code 
> Stmt([Return(Add((Name('anArg'), Const(1))))])
> 
> HTH,
> 
> /arg
> 
> 
> On Dec 7, 2004, at 11:14 PM, Caleb Hattingh wrote:
> 
>> Andy
>>
>> thx for that.  I had a file called 'tktest.py' lying around, and I did:
>>
>> '>>> a = compiler.parseFile('tktest.py')
>>
>> And "a" looks something like this:
>>
>> ***
>> Stmt([Import([('Tkinter', None)]), Function(None, 'add_rows', ['w', 
>> 'titles', 'rows'], [], 0, None, 
>> Stmt([Discard(CallFunc(Getattr(Name('w'), 'configure'), 
>> [Keyword('state', Const('normal'))], None, None)), For(AssName('r', 
>> 'OP_ASSIGN'), Name('rows'), Stmt([For(AssTuple([AssName('t', 
>> 'OP_ASSIGN'), AssName('v', 'OP_ASSIGN')]), CallFunc(Name('zip'), 
>> [Name('titles'), Name('r')], None, None), 
>> Stmt([Discard(CallFunc(Getattr(Name('w'), 'insert'), [Const('end'), 
>> Mod((Const('%s:\t%s\n'), Tuple([Name('t'), Name('v')])))], None, 
>> None))]), None), Discard(CallFunc(Getattr(Name('w'), 'insert'), 
>> [Const('end'), Const('\n')], None, None))]), None), 
>> Discard(CallFunc(Getattr(Name('w'), 'configure'), [Keyword('state', 
>> Const('disabled'))], None, None))])), Assign([AssName('app', 
>> 'OP_ASSIGN')], CallFunc(Getattr(Name('Tkinter'), 'Tk'), [], None, 
>> None)), Assign([AssName('t', 'OP_ASSIGN')], 
>> CallFunc(Getattr(Name('Tkinter'), 'Text'), [Name('app'), 
>> Keyword('state', Const('disabled'))], None, None)), 
>> Discard(CallFunc(Getattr(Name('t'), 'pack'), [], None, None)), 
>> Assign([AssName('info', 'OP_ASSIGN')], List([List([Const('Ali'), 
>> Const(18)]), List([Const('Zainab'), Const(16)]), 
>> List([Const('Khalid'), Const(18)])])), 
>> Discard(CallFunc(Name('add_rows'), [Name('t'), List([Const('Name'), 
>> Const('Age')]), Name('info')], None, None)), 
>> Discard(CallFunc(Getattr(Name('app'), 'mainloop'), [], None, None))])
>> ***
>>
>> Pretty impressive :)
>>
>> Do you know of more batteries that can process this stuff further, for 
>> interest sake (and maybe the OP)?
>>
>> thx again
>> Caleb
>>
>>
>> On Tue, 7 Dec 2004 15:57:16 -0500, Andy Gross <andy at andygross.org> wrote:
>>
>>>
>>> You'll want to use the "compiler" package.  compiler.parseFile will 
>>> return an AST that you can inspect (which is not really 'reflection', 
>>> btw).
>>>
>>> /arg
>>
>> -- 
>> http://mail.python.org/mailman/listinfo/python-list
> 
> 



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