On Thursday, 13 November 2014 at 12:01:33 UTC, Ola Fosheim
Grøstad wrote:
On Thursday, 13 November 2014 at 11:44:31 UTC, Manu via
Digitalmars-d wrote:
I don't follow how you associate that opinion with
implementation of
scope.
I don't like semantics where I have to state that the
parameters and the function should be "pure". It should be
opposite. Say, if you have an array on the stack, then I'd like
to take a slice of it and send it to a function to compute a
sum(). But, I don't want the type system to prevent me from
doing it because the author of sum() forgot to add "scope" to
the parameter.
What is the difference between a function that is annotated as
"pure" and a function where all input is "scope"? This is
backwards!
Function signatures should not say "I am playing nice…", that
should be the default. They should say "watch out, I'm stealing
your stuff!".
I agree with this in principle, but it is unrealistic for D2.
This is stuff that can go into a future D3, together with @safe
by default, pure by default, and maybe immutable by default. But
that doesn't mean that it shouldn't be introduced in D2 already,
so that we can gain experience with it.
That said, it might not be so bad with `scope`. The latest
iteration of the proposal has been simplified a lot; scope
annotations will mostly be needed for function signatures, and
explicit owners are only allowed there. There's also some
potential for inference with templates.
