Re: [Pyparsing] Indefinitely recursive grammar because of unaryoperation in operatorPrecedence()

[Paul M. <pt...@au...>]

Gustavo -

Once again, your attachments are not coming through the list server, so I
suggest you post to the pyparsing pastebin at pyparsing.pastebin.com.

But I'll take a wild guess here.  I think "not" may be being interpreted by
your grammar as a valid identifier.  Make sure your definition of operand
includes something like:

# be sure to define these as Keywords, and not Literals
# if defined as Literals, an identifier like "notMyFathersOldsmobile"
# would process the leading "not" as the "not" keyword
true_ = Keyword("true")
false_ = Keyword("false")
and_ = Keyword("and")
or_ = Keyword("or")
not_ = Keyword("not")

allKeywords = true_ | false_ | and_ | or_ | not_

identifier = ~allKeywords + Word(alphas, alphanums+"_")

operand = identifier | numeric_constant | quotedString


To double-check my theory, try using:

operand.setDebug()

And rerun your grammar to see if "not" is matching what you think it is
matching.

-- Paul