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From: ejp@bohra.cpg.oz (Esmond Pitt)
Newsgroups: comp.lang.misc
Subject: Re: Is there a Yacc file for PLI?
Keywords: yacc pli
Message-ID: <120@bohra.cpg.oz>
Date: 20 Nov 89 02:11:59 GMT
References: <14610@well.UUCP>
Reply-To: ejp@bohra.cpg.oz (Esmond Pitt)
Distribution: comp
Organization: Computer Power Group, Melb, Australia
Lines: 19

In article <14610@well.UUCP> sri@well.UUCP (Software Research Inc) writes:
>
>
>	We here at Software Research, Inc. are planning on working
>on a product that will require us to parse PLI code.  Does anyone
>have, or know where to get, a yacc-able version of the grammar for
>PLI?

You will find this a highly non-trivial task. There is no yacc-able
grammar for PL/1 because there are no reserved words; i.e. keywords are
only keywords in context & are otherwise identifiers. YACC does not
easily handle this case. (Consider IF IF THEN THEN ...)

The last PL/1 compiler I looked at had about 8 syntax analysis passes,
all hand-written.

-- 
Esmond Pitt, Computer Power Group
ejp@bohra.cpg.oz