Can't parse "a # not b", but parses "a # (not b)" and prints it as "a # not b"

Dear all,

as Stavros noted in this bug report
<https://sourceforge.net/p/maxima/bugs/4390/>, Maxima fails to parse this:

a # not b
Error: "Found LOGICAL expression where ALGEBRAIC expression expected"

However, a # (not b) with parentheses parses perfectly, but is printed *without
parentheses*. This means that Maxima cannot parse its own output. (The same
for =.)

*Proposed fix:*
In nparse.lisp, change lpos and rpos for the = and # operators from $expr
to $any. Also, increase the binding powers of  <, <=, >= and > from 80 to
85. Note that this is in accordance with most programming languages, where <,
<=, >= and > have a higher binding power than == and !=, for the exact same
reason of being able to compare logical expressions. Maxima currently has
them all the same.

If we make this change, the following expressions will parse directly
without requiring parentheses, building the exact same trees they already
do:

a # not b
a = not b
a = b = c (parses as (a = b) = c)
a > b = c (parses as (a > b) = c)
c = a > b (parses as c = (a > b), wouldn't parse with the original binding
powers)

Would this have any unintended side-effects?

Best regards
David Scherfgen

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