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<Paper uid="C86-1125">
  <Title>ON FORMALIZATIONS OF MARCUS' PARSER</Title>
  <Section position="2" start_page="0" end_page="0" type="intro">
    <SectionTitle>
1. Introduction
</SectionTitle>
    <Paragraph position="0"> In his 1JCA1-83 paper \[1\], R.C. Berwick suggested that the stripped down version of Marcus' parser \[4\] (i.e., with no features or transformations) can be formally characterized by LR(k,t) parsers \[7,8\]. Berwick's COLING-84 paper \[2\] seems to suggest that Marcus-style parsers may be adequately formalized by bounded context parsable BCP(m,n) grammars\[8,9\].</Paragraph>
    <Paragraph position="1"> In this paper we show that both classes of LR(k,t) and BCP(m,n) grammars are inadequate means to formalize Marcus' mechanism even when it is applied to parsing bare context-free grammars. We briefly describe a new class of unambiguous context-free grammars, LRRL(k), for which deterministic non-canonical bottom-up table driven parsers are generated automatically. These parsers employ k-symbol fully reduced right context in making parsing decisions. LRRL(k) grammars include as a subset tho;;e context-free grammars that arc parsablc by Marcus' partially topdegdown method.</Paragraph>
  </Section>
class="xml-element"></Paper>