lex query: "Too many right contexts"

[Inventor of micro-S]

In article <1527 at dalcs.UUCP> silvert at dalcs.UUCP (Bill Silvert) writes:
>Whenever I use a right context in a long lex program I get the message:
>	(Error) Too man right contexts
>Specifically, I am working on a cross-reference program for f77,
>which has lines like:
>	WRITE	;
>to ignore reserved words . . .

In the lexical analyzer for the compiler I am writing, I used to get some
message about exceeding some limit.  I never was able to figure out how to
change that limit.  (If I tried some number close to 980, I would get this
message, and if I tried the next number, lex would crash.  I was using a
Vax 11/750, and still am.)  What I ended up doing was to treat all the keywords
as normal identifiers, and then call a function to figure out if it was actually
a keyword or an identifier.  I suspect that having lex recognize keywords
directly makes it consume large amounts of memory, making it easy to exceed
its limits.
-----------------------------------------
Samuel A. Figueroa, Dept. of CS, Univ. of KY, Lexington, KY  40506-0027
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