Re: [PATCH] bootstrap: use a more consistent error reporting scheme.

[Jim Meyering]

Akim Demaille wrote:
> Le 6 juil. 2012 à 14:24, Jim Meyering a écrit :
>
>> Akim Demaille wrote:
>>> Le 6 juil. 2012 à 13:56, Jim Meyering a écrit :
>>>
>>>> Um... this is a good reason to post an adjusted patch.
>>>> What I meant was that it is fine to continue to print that diagnostic
>>>> on one line, but not using echo; using the new "warn".
>>>>
>>>> It should use warn, and warn should be defined as in init.sh.
>>>
>>> Ah, ok.  But the messages were already on several lines before,
>>> so you actually prefer to make the diagnostic less formatted?
>>>
>>> -if test $found_aux_dir = no; then
>>> -  echo "$0: expected line not found in configure.ac. Add the following:" 
>>> >&2
>>> -  echo "  AC_CONFIG_AUX_DIR([$build_aux])" >&2
>>> -  exit 1
>>> -fi
>>> +test $found_aux_dir = yes \
>>> +  || die "expected line not found in configure.ac. Add the following:" \
>>> +         "  AC_CONFIG_AUX_DIR([$build_aux])"
>>
>> Actually, using die above is fine.
>> However, I would like to keep bootstrap's warn and init.sh's warn_ 
>> compatible.
>
> So if I understand correctly die would take lines as arguments
> and warn would take words?  Or maybe I don't understand what you
> mean with "Actually, using die above is fine".  Maybe you mean
> making this diagnostic output a single line?

Sorry I haven't been clear enough.
die here should be like init.sh's die_ and take words, not lines.
That particular diagnostic wouldn't look too bad on one line.

>>> -          echo "$me: Error: '$app' version == $inst_ver is too old" >&2
>>> -          echo "       '$app' version >= $req_ver is required" >&2
>>> +          warn "Error: '$app' version == $inst_ver is too old" \
>>> +               "       '$app' version >= $req_ver is required"
>>>
>>> Or do you prefer reintroducing braces and several commands for a single,
>>> but multi-line, message?
>>
>> Converting separate arguments into separate lines seems wrong.
>> Inserting newlines is the job of a printf-like function.
>>
>> Options:
>>  - use printf 1>&2 ... or
>>  - use a printf-style variant, say warnf, that would be used like this:
>>
>>    warnf '%s\n' "Error: '$app' version == $inst_ver is too old" \
>>                 "       '$app' version >= $req_ver is required"
>
> Don't you mean warnf '%s\n%s\n'?

No, but if you think it's better, somehow...
I meant that warnf would be a very thin wrapper around printf:

    $ printf '%s\n' a b c
    a
    b
    c

> Or should warnf expect a single %s

or multiple %-directives:

    $ printf '%s - %s\n' a b c d
    a - b
    c - d

> in $1 and use $1 repeatedly on the remaining arguments?