I noticed that bison 3.0.4 does not complain about undeclared "text"
tokens in the grammar. They are automatically assigned a number but they
do not appear in the generated enum.
This is annoying because that makes syntax errors very difficult to find.
For example, consider the following grammar
===============
%defines
%define api.token.prefix {TOK_}
%token
END 0 "end of file"
ASSIGN ":="
IDENT "ident"
%%
%start stmt;
stmt: "ident" "=" "ident" ;
%%
===============
The error is that "=" should be ":=" in the stmt rule but bison 3.0.4 is
completely silent about it.
In the report, we can see that "=" is given the number 260
"end of file" (0) 0
error (256)
":=" (258)
"ident" (259) 1
"=" (260) 1
Of course, that number does not appear in the generated yytokentype:
enum yytokentype
{
TOK_END = 0,
TOK_ASSIGN = 258,
TOK_IDENT = 259
};
Is there a way to prevent an undeclared "token" to be silenty accepted
in the grammar?
Thanks
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