First, a personal thanks for taking the time to respond Amon. It's clear you have a strong understanding of Marpa and your response to this question and my previous questions have been exceedingly useful. I have been reading through the documentation but I am finding it difficult to find what I need as there is much to absorb.

You are correct that the 'read' call was in my code, it was missed in my copy/paste. I have edited the main post to reflect this change.

I had assumed that the behavior here was just something that I did not understand, not that Marpa was incorrect or faulty. Your response confirms this. So a couple of followup questions.

1) Given this information, it would seem to me that you should be able to differentiate between the parser exhausting the input as opposed to successfully parsing the entire grammar. Is there some way to determine this?

After a bit of thought, I'm assuming that determining what constitutes 'parsing the entire grammar' would be a difficult problem in and of itself considering the way a parse tree is created. Exhausting the input string is probably a reasonable indicator of a grammar having been parsed successfully.

2) How would you resolve the problem in example 2 assuming this was part of a more complex grammar? Considering you are locked into a greedy match behavior on a per token basis, this seems difficult to resolve.

In reply to Re^2: Marpa -- Partial grammar match does not result in failure by tj_thompson
in thread Marpa -- Partial grammar match does not result in failure by tj_thompson

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