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Re: Bison 3.3.2 released [stable]

From: Akim Demaille
Subject: Re: Bison 3.3.2 released [stable]
Date: Mon, 4 Feb 2019 12:28:49 +0100

> Le 3 févr. 2019 à 18:24, Frank Heckenbach <address@hidden> a écrit :
>>> My only suggestion is about the wording in this announcement
>>> (and also in the manual):
>> [...]
>> You are right, this is much better.  I'll install this:
>> [...]
> Thanks. However, this accouncement still contains the old wording,
> and the documentation (bison.texi:11672) similarly. Is this
> intentional or just an oversight?

:(  Stupid oversight...  I copied/pasted the bottom of the previous 
announcement, completely forgetting about the update...  As for the doc, I 
didn't remember it looked the same.  I propose the following change:

commit 8a1d89e07301a44a704be50fad1b6a39ff998448
Author: Akim Demaille <address@hidden>
Date:   Mon Feb 4 12:26:35 2019 +0100

    doc: clarify the purpose of symbol_type constructors
    Reported by Frank Heckenbach.
    * doc/bison.texi (Complete Symbols): Here.

diff --git a/doc/bison.texi b/doc/bison.texi
index 279b73d2..c241473b 100644
--- a/doc/bison.texi
+++ b/doc/bison.texi
@@ -11668,15 +11668,21 @@ symbol_type (int token, const int&, const 
 symbol_type (int token, const location_type&);
 @end example
-which should be used in a Flex-scanner as follows.
+Correct matching between token types and value types is checked via
address@hidden; for instance, @samp{symbol_type (ID, 42)} would abort.  Named
+constructors are preferable (see below), as they offer better type safety
+(for instance @samp{make_ID (42)} would not even compile), but symbol_type
+constructors may help when token types are discovered at run-time, e.g.,
-[a-z]+   return yy::parser::symbol_type (TOK_IDENTIFIER, yytext, loc);
-[0-9]+   return yy::parser::symbol_type (TOK_INTEGER, text_to_int (yytext), 
-":"      return yy::parser::symbol_type (':', loc);
-<<EOF>>  return yy::parser::symbol_type (0, loc);
+[a-z]+   @{
+           if (auto i = lookup_keyword (yytext))
+             return yy::parser::symbol_type (i, loc);
+           else
+             return yy::parser::make_ID (yytext, loc);
+         @}
address@hidden group
 @end example
 @sp 1

Sorry, and thanks!

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