Newbie: How can I use a string value for a keyword argument?

[Gary Herron]

Doug Morse wrote:
> Hi,
>
> My apologies for troubling for what is probably an easy question... it's just
> that can't seem to find an answer to this anywhere (Googling, pydocs, etc.)...
>
> I have a class method, MyClass.foo(), that takes keyword arguments.  For
> example, I can say:
>
> x = MyClass()
> x.foo(trials=32)
>
> Works just fine.
>
> What I need to be able to do is call foo() with a string value specifying the
> keyword (or both the keyword and value would be fine), something along the
> lines of:
>
> x = MyClass()
> y = 'trials=32'
> x.foo(y)        # doesn't work
>   
Keyword args are represented during the calling process as a 
dictionary,   You can create the dictionary yourself, and slip it into 
the calling arguments with a ** notation:

kw = {somestring:32}
x.foo(**kw)

Gary Herron

> or
>
> x.MyClass()
> y = 'trials'
> x.foo(y = 32)   # does the "wrong" thing
>
> Surely there's some way to use a string's value as the key for making a method
> call with a keyword argument?
>
> Just for completeness, my goal is simply to read a bunch of key/value pairs
> from an INI file (using ConfigObj) and then use those key/value pairs to set a
> (3rd party) object's parameters, which must be done with a call along the
> lines of "instance.set(key=value)".  Obviously, I could create a huge if..elif
> statement along the lines of "if y = 'trials': x.foo(trials=32); elif y =
> 'speed': x.foo(speed=12);" etc., but then the statement has to be maintained
> every time a new parameter is added/changed etc.  Plus, such a solution seems
> to me grossly inelegant and un-Pythonic.
>
> Thanks in advance for any and all assistance!
>
> Doug
>
>
>
>
>
>