> From: Taylor R Campbell <campb...@mumble.net> > Date: Thu, 3 Nov 2016 20:26:22 +0000 > > [...] > I was pleased to find only a couple spots needing patching to "pass > along multiple values". The team did good. The lusers may still get > sore, but our canon offered a good example. > > How do you know you got them all?
I don't. I was afraid I'd be tripping over many, surprised at so few (so far as getting through the build). > That excerpt is about (begin (values 1 2 3) ...). [repeat of 1st excerpt] > > [second excerpt] > > That excerpt is about (list (values 1 2 3)), which I strongly advise > that we report noisily. Is there a way for VALUES to distinguish them? > [...] > your change would cause the semantics of the code to silently change > from passing on all values to passing on only the first value. Yes, the "extension" I mentioned earlier: > I might be breaking things (again!). While I've removed our > restriction on VALUES (that it and only it return to CALL-WITH- > VALUES), I have also removed an "extension" that allowed e.g. cleanup- > noop-nodes to pass along multiple values as if they were one. It was > not a documented extension, yet losing it will break unwary code. > Perhaps just a mention in the release notes? I thought it was a bug, not a feature. Is fixing the bug now a bug, not a feature? > Right now in your branch, it seems that (list (values 1 2 3)) gives > the list (1) rather than an error. Yes. Right now the VALUES primitive in that branch cannot distinguish between (list (values...)) and (begin (values...)) as far as I know. If it does not require major changes to the compiler, I'd be happy to code VALUES for the distinction. _______________________________________________ MIT-Scheme-devel mailing list MIT-Scheme-devel@gnu.org https://lists.gnu.org/mailman/listinfo/mit-scheme-devel
