Re: GIT version: values writing

[ludo@gnu.org (Ludovic Courtès)]

Hi Hans,

Hans Aberg <haberg-1@telia.com> writes:

> There seems to be a bug in GIT version when writing the 'values' data
> type.
>   (list 2 (values 3 4) 5)
>   $1 = (2 3 5)

This behavior is correct: in Guile 1.9, multiple-value returns are
truncated any time the continuation expects fewer values.

Here, the ‘values’ call returns 3 values, but the location where it’s
called expects only 1, hence the automatic truncation.

> with the value 4 lost In guile-1.8.8, it would write
>   (2 #<values 3 4> 5)

The special “values” type in older Guile versions was an artifact of
Guile’s implementation of multiple value support; objects of that type
are normally invisible to user code, but they would show up in such
situations (R5RS doesn’t specify what to do in these cases, so it was
valid, but implementation-specific behavior.)

Thanks,
Ludo’.