The immediate error detection property does not even approach the scope of left-eideticism. The error detection property is only about detecting what the parser thinks is the error, which for a deterninistic parser is often not the actually error.
And left-eideticism is not limited to errors, real or supposed. Marpa knows *every* rule and symbol recognized or predicted to the left of the current location. For example, you could, when parsing HTML, stop Marpa and ask it for all the tables nested more than 3 level deep, either complete or in progress. More often useful is the Ruby Slippers technique, where the parser knows exactly what symbols are needed to continue. As another example, the technique in this blog post relied on Marpa's ability to tell the application the beginning and end of any rule recognized so far. To get an idea of the information available, you can look at the POD for the progress reports <http://search.cpan.org/dist/Marpa-R2/pod/Progress.pod>. This show the full detail available, which can be helpful for debugging a grammar. Applications will usually use information in a digested form. If you've been working within the framework of deterministic parsers, the amount of information available from the Earley tables can be surprising. Compared to left-eideticism, the immediate error detection property is parsing while blind-folded. On Wed, Nov 19, 2014 at 10:46 AM, <[email protected]> wrote: > Isn't *left-eideticism* the same thing as *immediate error detection > property* (as defined by Jacobs&Grune in "Parsing Technique. A Practical > Guide", 2nd edition, pages 248, 299, 524, 525, 625, 626)? > > -- > You received this message because you are subscribed to the Google Groups > "marpa parser" group. > To unsubscribe from this group and stop receiving emails from it, send an > email to [email protected]. > For more options, visit https://groups.google.com/d/optout. > -- You received this message because you are subscribed to the Google Groups "marpa parser" group. To unsubscribe from this group and stop receiving emails from it, send an email to [email protected]. For more options, visit https://groups.google.com/d/optout.
