Dear Shiro,

in case you can spare a minute or two, may you want to briefly review the second draft of SRFI 195 before finalization? I've added a number of introspection procedures following your request. The form just a minimal set as more multiple value procedures will land in a forthcoming SRFI for multiple values as we have discussed here.

Best regards,

Marc

Am Mo., 4. Mai 2020 um 23:21 Uhr schrieb Shiro Kawai <xxxxxx@gmail.com>:

Can it also have an interface to query how many values a given box is holding?

Without that, any generic code to deal with boxes must receive the unboxed values

as a list.  Although clever compilers may eliminate construction of intermediate lists

in some cases, it'll be easier if one can get the information (e.g. one can have fast-path

for single-valued box, or check the box argument and reject early if the passed box

has different values than expected.)