yyscan_t was not declared in this scope

[Jack Bates]

Hi, I'd like to include the header file that Bison generates in another 
C file, where I implement my actions -- so as to use the token type 
macros. Meanwhile I've used Flex to implement a reentrant scanner, so 
the first argument to yyparse() is a yyscan_t:

  %parse-param { yyscan_t scanner }

However, in addition to the token type macros, the header file contains 
the yyparse declaration:

  int yyparse(yyscan_t scanner);

So when I try to compile it, I get the following error:

  TsConfigGrammar.h:125:20: error: ‘yyscan_t’ was not declared in this 
scope

I can think of a couple ways around this -- what's the recommended solution?

Thanks!