View Review Details


Book:   lex & yacc
Subject:   lex & yacc, 2nd Edition Review
Date:   2003-09-10 14:42:29
From:   Emmet Caulfield
Rating:  StarStarStarStarStar


I have a copy of the 1st edition and recently downloaded the sample code.


I have to concur with Andy Wong Man Boon, above, that the sample code is pretty crummy. I downloaded the code because I'd a particular interest in the SQL grammar, and found that the sql1 example didn't compile, complaining about being unable to resolve yywrap(). After fixing this problem (either by linking with -lfl or putting in a substitute yywrap()), I then found that the executable gave:


<blockquote>


1: syntax error at FROM


SQL parse failed


</blockquote>


when fed SELECT foo FROM bar;!


Now, I'm no expert (otherwise I wouldn't have the book), but it seems to me that simple queries like this aren't allowed by the grammar in sql1.y. I got it to work by putting the following into the grammar:


<blockquote>


sql: query_exp


;


</blockquote>


How trustworthy can the code, or the book, be when this kind of simple mistake is made?


Emmet



See larger cover