Re: [PATCH 4/4] gettext-tools: use %define api.prefix

[Akim Demaille]

> Le 1 mai 2020 à 22:07, Bruno Haible <address@hidden> a écrit :
> 
> Hi Akim,
> 
>> This was introduced in Bison 2.6.
>> 
>> * gettext-tools/src/po-gram-gen.y: Use Bison's api.prefix instead of
>> handling renaming by hand.  New symbols would have been not renamed.
> 
> Thanks. One more thing I did not know about. Applied.
> 
> Note that Bison 3.0, not 2.6, is the minimum required Bison version for
> this change. With Bison 2.7.1, I get
> 
> po-gram-gen.y:22.20-29: erreur: erreur de syntaxe, {...} inattendu

Heck, you are right, I forgot about that.

At the beginning we only had one type of values for variables,
so they were all written like strings.  So indeed in 2.6 we
introduced `%define api.prefix "foo_"`.

But in 3.0 we introduced variable types, so that in addition
of `"foo"` (now for strings), there is `{foo}` (for code or snippets)
and `foo` (for keywords, i.e., enums if you wish).  Existing
variables such as api.prefix were "typed" appropriately, therefore
{foo_} rather than "foo_" in this case.

Of course we did not break compatibility: older variables are
"casted" when needed.

Therefore you have two options:

- require 3.0 and you're done

- require 2.6 and use api.prefix with `"foo_"`, but get warnings
  from -Wdeprecated.



FWIW, bison --update should correctly fix grammar files using
the old syntax to the current one.

Cheers!