Earley predict on complete input #109
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An original (maybe overeager!) optimization was included with Earley parsing. If there was no remaining input text, then no more predictions from the grammar were attempted. In most cases, this saves Earley a some work. But the BNF crate supports empty production rules. This invalidates this optimization, because an empty production may still be successful even with no remaining input text. This commit only removes this optimization built on that false assumption. It would be possible to reintroduce this improvement, but *only* for grammars without any empty productions.
shnewto
approved these changes
Sep 13, 2022
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An original (maybe overeager!) optimization was included with Earley parsing. If there was no remaining input text, then no more predictions from the grammar were attempted. In most cases, this saves Earley some work. But the BNF crate supports empty production rules. This invalidates this optimization, because an empty production may still be successful even with no remaining input text.
This commit only removes this optimization built on that false assumption. It would be possible to reintroduce this improvement, but only for grammars without any empty productions.
Closes #108