[m-rev.] for review: formatting of uints using string.format etc.

[Zoltan Somogyi]

On Sat, 23 May 2020 02:12:43 +1000 (AEST), Julien Fischer <jfischer at opturion.com> wrote:
> --- a/library/pprint.m
> +++ b/library/pprint.m
> @@ -463,6 +463,9 @@ group(X)                = 'GROUP'(doc(X)).
>  poly(s(S))              = text(string.format("%s", [s(S)])).
>  poly(c(C))              = text(string.format("%c", [c(C)])).
>  poly(i(I))              = text(string.format("%d", [i(I)])).
> +% XXX FIXME: replace the following line after the bootstrap compiler
> +% understands how to specialise format calls with uints.
> +poly(u(U))              = text(uint_to_string(U)).
>  poly(f(F))              = text(string.format("%f", [f(F)])).

This FIXME calls for a new synonym for compiler_sufficiently_recent
in compiler/options.m.

> --- a/library/string.format.m
> +++ b/library/string.format.m
> @@ -739,6 +822,9 @@ format_signed_int(Flags, MaybeWidth, MaybePrec, Int) = String :-
>      % Format an unsigned int, unsigned octal, or unsigned hexadecimal
>      % (u,o,x,X,p).
>      %
> +    % XXX we should replace most of this with a version that operates directly
> +    % on uints.
> +    %
>  :- func format_unsigned_int(string_format_flags, string_format_maybe_width,
>      string_format_maybe_prec, string_format_int_base, int) = string.
> @@ -894,6 +980,15 @@ format_unsigned_int(Flags, MaybeWidth, MaybePrec, Base, Int) = String :-
> +:- func format_uint(string_format_flags, string_format_maybe_width,
> +    string_format_maybe_prec, string_format_int_base, uint) = string.
> +
> +format_uint(Flags, MaybeWidth, MaybePrec, Base, UInt) = String :-
> +    Int = cast_to_int(UInt),
> +    String = format_unsigned_int(Flags, MaybeWidth, MaybePrec, Base, Int).

Do you intend to switch this around soon?

> index 080cb0b..1f026f7 100644
> --- a/tests/hard_coded/stream_format.exp
> +++ b/tests/hard_coded/stream_format.exp
> @@ -1 +1 @@
> -foo561a3.141000
> +foo561a3.1410001111
> diff --git a/tests/hard_coded/stream_format.m b/tests/hard_coded/stream_format.m
> index f9e7061..9aa432b 100644
> --- a/tests/hard_coded/stream_format.m
> +++ b/tests/hard_coded/stream_format.m
> @@ -18,5 +18,5 @@
>
>  main(!IO) :-
>       io.stdout_stream(Stdout, !IO),
> -     stream.string_writer.format(Stdout, "%s%d%c%f\n",
> -          [s("foo"), i(561), c('a'), f(3.141)], !IO).
> +     stream.string_writer.format(Stdout, "%s%d%c%f%u\n",
> +          [s("foo"), i(561), c('a'), f(3.141), u(1111u)], !IO).

Not related directly to this diff, but wouldn't it be easier to
check the output if there was a space or some other divider between
the values being printed?

I did not check the expected outputs of the string_format test cases,
since I forgot the meaning of some of the flags. I hope you *did*
check them.

Apart from the issues mentioned above, the diff is fine.

Zoltan.