Debug help - ! in data sharing concurrency

[Andy Valencia]

On Sunday, 31 August 2025 at 12:44:33 UTC, Brother Bill wrote:
> FWIW, given that D supports Message Passing Concurrency, is 
> Data Sharing Concurrency just there for D completeness, for 
> those that want to live close to the iron.

Speaking as a guy who did Unix kernel SMP for years, there are 
times when you just need shared memory, spinlocks, atomic 
lock->semaphore transitions, atomic operations (increment, 
compare/exchange, etc.).  D has all of'em, and I made sure they 
worked when I was first looking at D.

> It would seem that Message Passing Concurrency should be our 
> first, second and third choice for concurrency.

Indeed.  As the Golang folks have also noted, message passing is 
almost inevitably a more productive and less error prone way to 
coordinate parallel threads.  If, some day, you find your 
parallel app dying under the overhead of all the messaging--you 
can keep shared memory programming in mind as a possible 
alternative.

Andy