Adding to a module's __dict__?
Dave Angel
davea at ieee.org
Tue Mar 2 16:23:34 EST 2010
Terry Reedy wrote:
> On 3/2/2010 11:18 AM, John Posner wrote:
>> On 3/2/2010 10:19 AM, Roy Smith wrote:
>>>
>>> Somewhat sadly, in my case, I can't even machine process the header
>>> file. I don't, strictly speaking, have a header file. What I have is
>>> a PDF which documents what's in the header file, and I'm manually re-
>>> typing the data out of that. Sigh.
>
> There are Python modules to read/write pdf.
>
>> Here's an idea, perhaps too obvious, to minimize your keystrokes:
>>
>> 1. Create a text file with the essential data:
>>
>> XYZ_FOO 0 The foo property
>> XYZ_BAR 1 The bar property
>> XYZ_BAZ 2 reserved for future use
>>
>> 2. Use a Python script to convert this into the desired code:
>>
>> declare('XYZ_FOO', 0, "The foo property")
>> declare('XYZ_BAR', 1, "The bar property")
>> declare('XYZ_BAZ', 2, "reserved for future use")
>>
>> Note:
>>
>> >>> s
>> 'XYZ_FOO 0 The foo property'
>> >>> s.split(None, 2)
>> ['XYZ_FOO', '0', 'The foo property']
>
> Given that set of triples is constant, I would think about having the
> Python script do the computation just once, instead of with every
> inport. In other words, the script should *call* the declare function
> and then write out the resulting set of dicts either to a .py or
> pickle file.
>
> tjr
>
>
There have been lots of good suggestions in this thread. Let me give
you my take:
1) you shouldn't want to clutter up the global dictionary of your main
processing module. There's too much risk of getting a collision, either
with the functions you write, or with some builtin. That's especially
true if you might later want to use a later version of that pdf file.
Easiest solution for your purposes, make it a separate module. Give it
a name like defines, and in your main module, you use
import defines
print defines.XYZ_FOO
And if that's too much typing, you can do:
import defines as I
print I.XYZ_FOO
Next problem is to parse that pdf file. One solution is to use a pdf
library. But another is to copy/paste it into a text file, and parse
that. Assuming it'll paste, and that the lines you want are
recognizable (eg. they all begin as #define), the parsing should be
pretty easy. The results of the parsing is a file defines.py
Now, if the pdf ever changes, rerun your parsing program. But don't run
it every time your application runs.
If the pdf file were changing often, then I'd have a different answer:
2) define an empty class, just as a placeholder, and make one instance I
Populate a class instance I with setattrib() calls, but access
it with direct syntax, same as our first example.
DaveA
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