Mattias Engdegård <mattias.engdegard@gmail.com> writes:

[...]

> Either I misunderstood what a return value of `boolean` means, or that
> list is riddled with errors. The following functions are specified to
> return boolean in comp-known-type-specifiers but actually may return
> other values as well:
>
>   proper-list-p
>   buffer-modified-p
>   coordinates-in-window-p
>   custom-variable-p
>   file-locked-p
>   file-symlink-p
>   frame-visible-p
>   framep

Okay the attached should address these (please have a look if/when
you've time).

> and, since we have no guarantees about what file handlers actually return,
>
>   file-directory-p
>   file-exists-p
>   file-newer-than-file-p
>   file-readable-p
>   file-writable-p

Aren't the entries we have in agreement with the docstring?  If the
docstring is not in sync with the implementation we have either to fix
one o the other I think.

Thanks!

  Andrea