Re: NASL2 new operators & precedence

Is this change likely to affect the semantics of any of the
existing NASL scripts? I'm wondering if there are any that
rely on the old left-to-right ordering.

Cheers

Rich.

Michel Arboi wrote:
> I add three new operators:
> **  is the integer power (Fortran syntax)
> ^   is the logical xor
> 
>>>>is the unsigned / logical right shift (Java syntax)
>>>
>>> is now the signed right shift
>>
> (and by the way, there is no such thing as singed / unsigned left
> shift :)
> I also added %= which was missing
> 
> Here is the precedence I implemented now (from lower priority to
> higher):
> %right = += -= *= /= %= <<= >>= >>>=
> %left ||
> %left &&
> %nonassoc < > == != >= <= ><
> %left |
> %left ^
> %left &
> %nonassoc >> >>> <<
> %left + -
> %left * / %
> %left - (unary minus) ~
> %right **
> %nonassoc ++ --
> 
> 
> I know that this precedence is not like 
> - C; but C precedence really sucks
> - Java; but you cannot imagine how much I hate this language and the
>   marketing s** around it
> - Perl; but so many Perl operators are missing (and, or, etc.)
> 
> %nonassoc means that those constructions are rejected:
> x << y << z
> ++ x ++ 
> x ++ ++
> x > y > z
> "a" >< str >< "b"
> 
> %right means that 2**3**2 is parsed as 2**(3**2) = 2**9 and not
> (2**3)**2 = 8**2
> 


-- 
Richard Moore, Principle Software Engineer
Westpoint Ltd.