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Re: "eval vs operator.methodcaller" - which is better?

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Date Mon, 18 Mar 2013 14:58:44 +0100 (CET)
From Jean-Michel Pichavant <jeanmichel@sequans.com>
To Laxmikant Chitare <laxmikant.general@gmail.com>, python-list <python-list@python.org>
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Subject Re: "eval vs operator.methodcaller" - which is better?
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Xref csiph.com comp.lang.python:41417

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----- Original Message -----
> Hi,
> 
> I have a program that picks module and method name from a
> configuration file and executes the method. I have found two ways to
> achieve this.
> 
> Apporach 1:
> ---------------------------
> moduleName = 'mymodule'    #These two variables are read from conf
> file.
> methodName = 'mymethod'
> 
> import operator
> myModule = __import__('mymodule')
> myMethod = operator.methodcaller('mymethod')
> val = myMethod(myModule)
> print val
> ---------------------------
> 
> Apporach 2:
> ---------------------------
> moduleName = 'mymodule'    #These two variables are read from conf
> file.
> methodName = 'mymethod'
> 
> val = eval('myModule.' + methodName + '()')
> print val
> ---------------------------
> 
> Question: Which approach is better and why. Is there any other better
> way to do this?
> 
> Regards,
> Laxmikant
> --
> http://mail.python.org/mailman/listinfo/python-list
> 

Hi,

Any alternative to eval is always better than eval (aka eval is evil). 
Your code is not working in my python 2.5 env (operator has no methodcaller).

try something like

moduleName = 'mymodule'    #These two variables are read from conf file.
methodName = 'mymethod'
myModule = __import__(moduleName)
myFunc = getattr(myModule, methodName)
myFunc()


JM


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Re: "eval vs operator.methodcaller" - which is better? Jean-Michel Pichavant <jeanmichel@sequans.com> - 2013-03-18 14:58 +0100

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