On Borrow Checking

[Paul Backus]

On Sunday, 11 May 2025 at 18:23:56 UTC, Walter Bright wrote:
> On 5/11/2025 5:32 AM, Timon Gehr wrote:
>> On 5/10/25 06:13, Walter Bright wrote:
>>> The @live design was done in a manner to not need any new 
>>> syntax - it is an extra layer of error checking.
>> 
>> That would be giving too much credit.
>
> This is why I stopped working on D's borrow checker. It's all 
> been relentlessly negative. But I did get it to the point where 
> it proved that a borrow checker can work in D with zero changes 
> to the syntax (except marking a function as @live), and I'm 
> happy about that.

The reason for the negativity is that people do not want "a 
borrow checker." What they want is more powerful safety analysis. 
A borrow checker is merely one possible means of achieving that 
goal.

In business terms, this is a failure of "product-market fit." You 
are supplying something that there is no demand for. Even if it 
works perfectly, nobody is going to buy it.