dynamic class/module use? (like Java's forName)

Alex Hunsley lard at tardis.ed.ac.molar.uk
Sun Jul 18 20:53:32 CEST 2004

Paul McGuire wrote:

> "Alex Hunsley" <lard at tardis.ed.ac.molar.uk> wrote in message
> news:8glKc.31979$v7.20488 at fe2.news.blueyonder.co.uk...
> <snip>
>>Ok, the situation is that I am parsing a file that has "actions" (or
>>commands) embedded in it. Different actions cause different things to
>>happen to the file which is being preprocessed for something. Now, since
>>I will have many actions, and want my python to be extensible so other
>>users can add their own actions, rather than hard coding each action
>>like so:
>>  if (actionString == "blah"):
>>      blahThang = blah(constructor stuff)
>>      blahThang.doSomething()
>>  else if (actionString == "blah2"):
>>      blahThang2 = blah2(constructor stuff)
>>      blahThang2.doSomething()
>>  else if (actionString == "blah3"):
>>      blahThang3 = blah3(constructor stuff)
>>      blahThang3.doSomething()
>>  else if (actionString == "blah2"):
>>   # etc etc
> <snip>
> Alex,
> Have a look at how pyparsing (http://pyparsing.sourceforge.net) supports the
> attachment of actions to parse expressions within a grammar.
> -- Paul
Interesting, Paul! thanks for link.


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