🚀 go-pugleaf

about a month ago, i asked about using multiple parsers

my bug report was for bison version 1.10,
version 1.19 does not have that bug any more

the more interesting question was about multiple parsers and lexers -
i received useful information immediately from Kevin Burton and
Kevin Rodgers

their hints led me to look for yyrestart,
and then to a newer version of flex that has yyrestart
(version 2.3)

ok, here is the problem and the solution (so far) -
i have multiple lexers and multiple parsers in the same address space
(on a sparcstation),
so i need to separate the global symbols they use,
and also each one may be called at several times,
to read a different file each time,
so i need to initialize them appropriately

it turns out that 'yyrestart' easily handles the second problem
(though it fails if i call yyrestart before the first call to the parser,
so each of my parsers need to identify the first call,
which is irritating),
but none of the suggestions solves the first one
(it was perhaps not clear that i did not intend to catenate the several files,
but rather to read them as different parses) -

i already had include files that define the leftover globals in the parsers
and lexers to different things
(my choice of flex and bison over lex and yacc was exactly because
the gnu programs had made most of the tables static),
but the new version of flex added several more symbols
(having to do with buffers mainly) -

these are the interceptions i have so far,
but i needed to look at the generated code to find them

/*definitions to intercept flex variable names*/
#define yyin yZZin
#define yyout yZZout
#define yytext yZZtext
#undef YY_DECL
#define YY_DECL yZZlex()
#define yyrestart yZZrestart
#define yy_switch_to_buffer yZZ_switch_to_buffer
#define yy_load_buffer_state yZZ_load_buffer_state
#define yy_create_buffer yZZ_create_buffer
#define yy_delete_buffer yZZ_delete_buffer
#define yy_init_buffer yZZ_init_buffer
/* I don't know why these are external in the generated lexer */
#define yyleng yZZleng
#define yylval yZZlval

/*definitions to intercept bison variable names*/
#define yylex ZZlexer
#define yyparse ZZparse
#define yydebug yZZdebug
#define yyerror ZZyyerr
/* I don't know why these are external in the generated parser */
#define yychar yZZchar
#define yylval yZZlval
#define yylloc yZZlloc
#define yynerrs yZZnerrs