is this a valid import sequence ?

Scott David Daniels scott.daniels at acm.org
Sat Jun 23 20:03:03 CEST 2007


Stef Mientki wrote:
> ... I've defined a class, like this, ...
> 
> class T6963_device (tDevice):
>     def __init__ (self):
>         global LCD
>         LCD = self
> ... In the same module I've a function,
> that runs a method of the above class instance, ...
> 
> def Write_LCD_Data ( data ):
>     global LCD
>     LCD.Write_Data ( data )

The global statement in Write_LCD_Data is completely unnecessary.  The
only time you need "global" is if you want to reassociate the global
name to another object (such as LCD = LCD + 1 or whatever).  You only
read the global name-to-object mapping (though you may be using methods
on the named object to alter the referenced object).  You only need
"global" when you need to "write" (re-bind) the global name-to-object
mapping.

--Scott David Daniels
scott.daniels at acm.org



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