Re: [WIP PATCH for Dlang support] d: token constructors

[Adela Vais]

Hello Akim,

În mie., 20 ian. 2021 la 08:08, Akim Demaille <akim.demaille@gmail.com> a
scris:

> Hi Adela,
>
> > Le 19 janv. 2021 à 23:54, Adela Vais <adela.vais99@gmail.com> a écrit :
> >
> > Hello,
> >
> > I need some help with the patches I am writing.
> > I talked today with Akim and I am sending the WIP patches I have as
> attachments. If it is easier, here is a Github link [1].
> >
> > Thank you, Akim, in advance, for your help.
>
> Could you please provide a branch where the example is using variants?  I
> know it will fail, but that's the point: I'd like to have exactly the
> problem to solve.
>

I added another commit on the branch:
https://github.com/adelavais/bison/tree/token-constructors-squash


> Thanks in advance!


> PS/  Please, *all* the macros in tests/ should be named AT_*.  And it
> should not be very hard to fuse these two macros:
>
> # YYLEX_RETURN_WITH_VALUE
> m4_define([YYLEX_RETURN_WITH_VALUE],
> [AT_TOKEN_CTOR_IF([[return Symbol.]AT_TOKEN_PREFIX[$1]($2
> AT_LOCATION_IF([[, location]])[);]],
>                   [[return Symbol(TokenKind.]AT_TOKEN_PREFIX[$1,
> $2]AT_LOCATION_IF([[, location]])[);]])]
> )
>
> # YYLEX_RETURN_WITHOUT_VALUE
> m4_define([YYLEX_RETURN_WITHOUT_VALUE],
> [AT_TOKEN_CTOR_IF([[return
> Symbol.]AT_TOKEN_PREFIX[$1](AT_LOCATION_IF([[location]])[);]],
>                   [[return
> Symbol(TokenKind.]AT_TOKEN_PREFIX[$1]AT_LOCATION_IF([[, location]])[);]])]
> )
>
> into one.  Untested, but that's the idea:
>
>
> # AT_YYLEX_RETURN
> # ---------------
> m4_define([AT_YYLEX_RETURN],
> [return dnl
> AT_TOKEN_CTOR_IF(
>   [[Symbol.]AT_TOKEN_PREFIX[$1](m4_ifval([$2], [$2 ])AT_LOCATION_IF([[,
> location]])[);]],
>   [[Symbol(TokenKind.]AT_TOKEN_PREFIX[$1[]m4_ifval([$2], [,
> $2])]AT_LOCATION_IF([[, location]])[);]])
> ])
>
>
> In case you're wondering why "$1[]m4_ifval" instead of "$1m4_ifval", it's
> to avoid that tokens get pasted together.  If $1 is "foo", then
> "$1my_ifval" yields "foom4_ifval", which is not a macro, so m4 will just
> paste that in the output.  With the '[]' m4 will see 'foo[]m4_ifval', and
> process first 'foo', then '[]' (giving nothing) and finally 'm4_ifval(...)'.
>
>
I tried to combine them, and I did not put the '[]'. That explains why it
failed. I will modify the function for the final version of the patch.

Thank you again, Akim.

Adela