Re: if then else shift/reduce Syndrome

| Tarn Burton <tarnwb@holly.colostate.edu writes:
| >Does anyone know how to get rid of the bison shift/reduce conflict in
| >the C if then else.
|
| Yes, classify statements as open or closed.


...


| open-if : if-query open-statement
| | if-query closed-statement else open-statement
| closed-if : if-query closed-statement else closed-statement


I remember in the early days of the ANSI C committee (before it was
ISO-ized, probably about 10 years ago), when I tried doing this with
the then current ANSI grammer. It blew away the parser generator's
table size (probably V7 yacc if memory serves, since I didn't know
about GNU back then) in that it basically doubled the amount of states
for the statements. I decided to leave well enough alone, because as
somebody mentioned, almost all parser generators (ie, all usable ones)
will do what you want, in favoring the shift over the reduce.


--
Michael Meissner, Cygnus Support (East Coast)
Suite 105, 48 Grove Street, Somerville, MA 02144, USA
meissner@cygnus.com, 617-629-3016 (office), 617-629-3010 (fax)
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