[TUHS] Archaic yacc C grammar

Lars Brinkhoff lars at nocrew.org
Mon Oct 29 17:31:24 AEST 2018


Steve Johnson wrote:
> Looking at the reserved words, there is one, ENTRY, that I've never
> heard of (although FORTRAN had an ENTRY statement), and there is
> STRUCT but no UNION. Also, he uses val= instead of $$=. There don't
> seem to be any nontrivial assignment ops (neither += or =+).

This is for Snyder's C compiler.  There is something called =op which
is guess is for =+ etc.

> I'm guessing either Al wrote it from scratch or based it on some other
> similar program.

Looks like you're right.  I found this in another file, so it would seem
he wrote it back at MIT:

  "The original YACC was designed and implemented on a PDP-11/45 and a
  Honeywell 6000 by S. C. Johnson at Bell Laboratories.  The version
  described in this paper was implemented on the PDP-10 by Alan Snyder.



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