How to set custom locals for function call?

[Terry Reedy]

On 9/1/2020 5:58 PM, Andras Tantos wrote:
> 
> On 9/1/2020 12:41 PM, MRAB wrote:

>> CPython is able to identify all of the local names of a function and, 

Note >>>of a function<<<.

>> basically, for reasons of efficiency, it uses slots for the local 
>> names instead of an actual dict. 'locals()' just returns a dict that 
>> represents those local names and their current values, but modifying 
>> that dict has no effect on the actual local names. In short, there 
>> isn't really a local dict that you can replace.

This applies to code in a function (def statement or lambda expression) 
and only that.

[Snip experiments with non-function code at >>> prompt.]

> In other words, I can indeed change the value of a local variable 
> through the locals() dict.

This is true for code that is not part of a function body, which is top 
level code and class code that is not part of a method body.


-- 
Terry Jan Reedy