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From: laplante.p@gmail.com
Newsgroups: comp.compilers
Subject: Error message with bison and flex
Date: Mon, 7 Apr 2014 22:36:46 -0700 (PDT)
Organization: Compilers Central
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Sometime the text return from a syntax error is very short.

I would like to output 5 lines before the error and
5 lines after the error.

Is this possible without affecting the error message.

If I used input to read the next 5 lins, the message won't be the same and
I don't want to always accumulate the 5 lines before, it will add a lot of overhead to the lexical analyser.

Tx
[The way I'd do it would be to write my own YY_INPUT() that slurps in
the whole file to a buffer when it starts and hands the input to the
lexer a line at a time, so it knows what line it's on.  If there's an
error, it can then scan forward and backward in the file buffer to find
the five lines each way. -John]