January 2013
Intermediate to advanced
328 pages
8h 5m
English
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Chapter 9Error Reporting and Recovery
As we develop a grammar, there will be lots of mistakes to fix just like any piece of software. The resulting parser won’t recognize all valid sentences until we finish (and debug) our grammar. In the meantime, informative error messages help us track down grammar problems. Once we have a correct grammar, we then have to deal with ungrammatical sentences entered by users or even ungrammatical sentences generated by other programs gone awry.
In both situations, the manner in which our parser responds to ungrammatical input is an important productivity consideration. In other words, a parser that responds with “Eh?” and bails out upon the first syntax error isn’t very useful for us during development or ...
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