[Caml-list] I never succeeded in using Format

[Matthieu Dubuget <matthieu.dubuget@gmail.com>]

Is the following behaviour expected, or a misunderstanding of mine?

In short, I'd like to use the Format module to prepare an
output inside a Buffer.t. But a basic <hov> box does not
break lines as I would expect, while printf does.

OCaml version 4.01.0

# open Format;;
# printf "@[<hov0>111,@,222,@,333,@,444,@,555,@,666@]@.";;
111,222,333,444,555,666
- : unit = ()
# set_margin 9;;
- : unit
= ()
# printf "@[<hov0>111,@,222,@,333,@,444,@,555,@,666@]@.";;
111,222,
333,444,
555,666
- : unit
= ()
# sprintf "@[<hov0>111,@,222,@,333,@,444,@,555,@,666@]@.";;
- : string
=
"111,222,333,444,555,666\n"

Why doesn't sprintf exhibit the same behaviour as printf?
Trying with fprintf…

# fprintf str_formatter "@[<hov0>111,@,222,@,333,@,444,@,555,@,666@]@.";;
- : unit
= ()
# flush_str_formatter ();;
- : string
=
"111,222,333,444,555,666\n"

-- 
Matthieu Dubuget