Re: Tail call elimination

[Paul Smith]

On Mon, 2020-05-18 at 21:40 -0400, Daniel Herring wrote:
> This decision causes a difficult and error-prone ambiguity when the
> return value is really true and empty.  For example, the operation
> succeeded and the result was "", versus the operation failed and thus
> returned "".  So Scheme added separate #t and #f values, C++ added
> true and false keywords, newer languages are adding an
> "optional/maybe" construct, etc.
> 
> The present Make behavior is perfect for things like dependency
> lists. However, it feels limiting for other use cases.

I would prefer to talk about concrete issues so we can consider them. 
I personally haven't run into situations where the fact that "" equates
to false is a problem but obviously others may have very different
experiences.

I'm really reluctant to start adding new higher-level language features
to GNU make unless there is a clear and obvious need that can't be
reasonably addressed any other way.