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Re: Pre-RFC Deep constants

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Martijn Lievaart
March 9, 2023 20:21
Re: Pre-RFC Deep constants
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Op 09-03-2023 om 21:14 schreef Ovid:
> On Thu, Mar 9, 2023 at 8:59 PM Dan Book <> wrote:
>     On Thu, Mar 9, 2023 at 2:50 PM Paul "LeoNerd" Evans
>     <> wrote:
>         To me what people are looking for is read only structures.
>         Thus 1. we need an actual read only mechanism for hashes
>         (restricted hashes are too restrictive for this purpose), and
>         2. in your example the declaration would cause @nums to also
>         become read only.
> Causing @nums to be read-only sounds like a good idea, actually. 
> Immutable data is often a huge win. The downside is when someone tries 
> to mutate @nums. We'd want a mechanism to tell the developer how and 
> where the variable became read-only. That introduces its own set of 
> problems, particularly if it's happened multiple times.

I think that would lead to very surprising behaviour. If @num itself is 
not const, I would expect this construct to either die, or make the 
reference RO but not @num itself.


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