[Python-Dev] Re: Compiler treats None both as a constant and variable

[Terry Reedy]

"Raymond Hettinger" <raymond.hettinger@verizon.net> wrote in message
news:002001c2f636$77ad2ce0$e60ca044@oemcomputer...
> >>> def f():
>  None
>
> >>> dis(f)
> 2           0 LOAD_GLOBAL              0 (None)
>               3 POP_TOP
>               4 LOAD_CONST               0 (None)
>               7 RETURN_VALUE
>
> >>> None = 1
> <stdin>:1: SyntaxWarning: assignment to None
> >>> f() == None
> False
>
>
> Is this a bug?

If one understands (as I do) the default return 'None' to mean the
singleton NoneType object that the name 'None' is assumed to be bound
to in the docs and which it is bound to on startup, then no.

> Should the compiler use the GLOBAL in both places?
> Or, is it reasonable to use CONST in both places?

I understood the latter to be the plan after a sufficient warning
period.

TJR