I'm going to stick with the -> convention for SRFI 189 at least, with explanatory text like this:

This SRFI supports converting Maybes and Eithers to other Scheme objects.  It also provides for converting the usual protocol for using Maybe and Either to alternative protocols historically used in Scheme (and other Lisps).  An example would be the protocol of returning a specific true value on success and #f on failure.  The notation "->" is used for both kinds of conversions.

I haven't read 195 in enough detail to know if it's appropriate there.

On Tue, Jun 9, 2020 at 4:39 AM Marc Nieper-Wißkirchen <xxxxxx@nieper-wisskirchen.de> wrote:
Am Do., 4. Juni 2020 um 18:39 Uhr schrieb Marc Nieper-Wißkirchen

> I don't like the "values-> ..." convention. That it has to be syntax

Despite the fact that I have initially proposed it myself as well...
but I didn't give it enough thought then.

> is a minor thing. The problem is that we use "... -> ..." when mapping
> objects of one type to objects of another type. However, there is such
> a thing as a "values" type. Assuming this leads to all the confusion
> we have had on the mailing list of SRFI 189 and also here, I think.