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LALR look-ahead sets from item right context grammar?

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From Richard Rogers <rprogers@seanet.com>
Newsgroups comp.compilers
Subject LALR look-ahead sets from item right context grammar?
Date Sat, 28 Feb 2026 13:43:17 +0000
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Qwen3-coder just pointed out that what I've described is actually "LALR(1)
with context-sensitive look-aheads," also known by a couple other names. To
get true LALR(1), you'd have to take the union of the FIRST(RCG(i,j)) over
states j containing item i. But that seems silly since it's better and less
code without doing the union :)

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LALR look-ahead sets from item right context grammar? Richard Rogers <rprogers@seanet.com> - 2026-02-07 01:42 +0000
  LALR look-ahead sets from item right context grammar? Richard Rogers <rprogers@seanet.com> - 2026-02-28 13:43 +0000

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