Some language proposals.

Anton Vredegoor anton at vredegoor.doge.nl
Wed Feb 25 16:02:54 CET 2004


Antoon Pardon <apardon at forel.vub.ac.be> wrote:

>I don't see much difference between a function changing a higher up
>variable that is global or just in between.

If you want a function with its own namespace, that is already
possible as you showed yourself in an earlier post. On the other hand,
if a function has its own namespace what is the difference between a
function and a class? Why not use a class in the first place?

Remember that "global" is just a way for a function to tell the
interpreter that this variable belongs to the global namespace. 

There is some inconsistency if one has a function inside a function
and that function has a global 'x' but the outer function doesn't have
a global 'x'. Modifications of 'x' from the deepest function do not
reach the global namespace, in fact they do not even reach the
namespace of the containing function.

Only if both functions have a global 'x' the name is visible at the
global and intermediate level. 

However there is already a mechanism to solve these kind of problems:
namespaces! Why not use them?

>>   a,b = A.a,A.b
>
>Well maybe my wording was off, but this doesn't accomplisch what I
>want since after your statement followed by: a = new_value; A.a will
>not be changed.

For that to work you'd have to imbue names with new magical powers.
They would have to have some way of knowing who their fellow holders
are with whom they share their objects and inform them about their new
responsibilities.

The fellow objects would need some instructions as to how to handle
such things. Should they hold on to their previous bindings or let go
and use the new objects? Maybe some automatic message passing between
objects "behind the covers" would be necessary. Maybe it's a great
idea or maybe we would get hit over the head with a stick. I don't
know.

By the way, would it then be really, really black magic to be able to
call an object by its *real* name and force all holders to obey? One
ring to rule them all!

... much, much, later ...

Message from your Atoned Governor.

Ok, after finally having relinquished the ring of power and freely
dropping it into the crater, I would like to make a public
announcement. 

It is a really bad idea to indiscriminately rip the structure and
inner cohesion and the "whole is more than the sum of the parts"
quality of existing cooperations of objects apart in order to gain
access to a little trinket, and from now on I will desist from such
actions until there is a way to replace the lost objects with
functionality that is the same or better, according to the judgement
of said cooperations, in order not to disrupt working ecosystems. 

Anton



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