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To: python-list@python.org
From: Dave Angel <davea@davea.name>
Subject: Re: exec and locals
Date: Wed, 26 Feb 2014 23:20:10 -0500 (EST)
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Xref: csiph.com comp.lang.python:67112

 Steven D'Aprano <steve@pearwood.info> Wrote in message:
> On Wed, 26 Feb 2014 14:46:39 +0100, Peter Otten wrote:
> 
>> Steven D'Aprano wrote:
>> 
>>> I have to dynamically generate some code inside a function using exec,
>>> but I'm not sure if it is working by accident or if I can rely on it.
>>> 
>> I eventually settled on some 
> code that works something like this:
> 
> 
> def factory():
>     blah blah blah
>     try:
>         exec("""def inner():
>                     

Before I would use exec,  I'd look hard at either generating a
 source file to import,  or using a preprocessor.  And if this
 code was to be installed,  make the version choice or the
 preprocess step happen at install time.

I once implemented a system that generated 20k lines of C++ header
 and sources. And the generated code was properly indented and
 fairly well commented. 



-- 
DaveA