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Date: Fri, 10 Feb 2012 03:11:52 -0800 (PST)
From: mloskot <mateusz@loskot.net>
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Subject: Re: Read-only attribute in module
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Terry Reedy wrote
> 
> On 2/9/2012 6:43 AM, Mateusz Loskot wrote:
>> import xyz print(xyz.flag)  # OK
>> xyz.flag = 0 # error due to no write access
> 
> Why prevent that? If you called it 'FLAG', that would indicate that it 
> is a constant that should not be changed. While Python make some effort 
> to prevent bugs, it is generally a 'consenting adults' language.
> 

Terry,

The intent of xyz.flag is that it is a value set by the module internally.
xyz is a module wrapping a C library.
The C library defines concept of a global flag set by the C functions at
some events,
so user can check value of this flag.
I can provide access to it with function: xyz.get_flag()
But, I thought it would be more convenient to have a read-only property in
scope of the module.

Sometimes, especially when wrapping C code, it is not possible to map C API
semantics to Python concepts as 1:1.

-----
-- 
Mateusz Loskot
http://mateusz.loskot.net
--
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