Last problem is solved

I wrote recently with a question about mapping from a found token back
to that token's point in the input stream. I solved it on my own in
the meantime.


The solution was basically as follows:


- Maintain a pointer to the head of the string to be parsed (I am
using an API that inputs string data, not a file), "s_input"
- Maintain a running total of bytes, "n_offset", fed to the lexer as a
static variable updated within the input() function
- Use the variables in YY_CURRENT_BUFFER and do a little pointer
arithmetic to extract the desired information, as follows:


inline const char * buf_offset()
{
return s_input + (in_offset - (YY_CURRENT_BUFFER)->yy_n_chars) +
(yytext - (YY_CURRENT_BUFFER)->yy_ch_buf);
}


Thanks


Eric

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