On Borrow Checking

[Paul Backus]

On Monday, 12 May 2025 at 13:45:04 UTC, jmh530 wrote:
> But I think "what people want" and "what's the goal here" are 
> two different kinds of questions. What people want is more 
> powerful safety analysis. But the reason why Walter started 
> working on this was that he saw safety as becoming a bigger 
> issue in programming languages, most notably with Rust gaining 
> traction, and wanted to help D compete on that basis.

Here, you say that the goal of @live is to compete with Rust on 
safety.

> So I think one thing that has Walter frustrated is that he 
> wants to be able to say D has a borrow checker when someone 
> asks, but the actual users don't want something unless it 
> actually enables the more powerful safety analysis.

Here, you say that the goal of @live is "to be able to say D has 
a borrow checker."

The problem is that these are not the same goal. Walter's work on 
@live has (arguably) succeeded in advancing goal #2, but it has 
done nothing to advance goal #1.

Personally, I believe that goal #1 is much more important than 
goal #2, and that spending effort to pursue #2 while ignoring #1 
is a mistake. If Walter disagrees, I can accept that, although I 
would like to at least see him make the positive case for why 
goal #2 is worth pursuing on its own.