Context-free multilanguages

Donald E. Knuth

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arXiv · cs/9301115

Context-free multilanguages

Donald E. Knuth

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Abstract

This article is a sketch of ideas that were once intended to appear in the author's famous series, "The Art of Computer Programming". He generalizes the notion of a context-free language from a set to a multiset of words over an alphabet. The idea is to keep track of the number of ways to parse a string. For example, "fruit flies like a banana" can famously be parsed in two ways; analogous examples in the setting of programming languages may yet be important in the future. The treatment is informal but essentially rigorous.

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BibTeX RIS

Donald E. Knuth. 1991-12-01. Context-free multilanguages. https://arxiv.org/abs/cs/9301115

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