Re: ISSTRICT behavior

Martijn van Oosterhout wrote:
> On Thu, May 04, 2006 at 12:29:30AM -0700, Don Y wrote:
>> OTOH, if the function could *abort* it's invocation, then
>> I don't have to worry about return values.  It is a closer
>> model to the STRICT behavior -- instead of aborting the
>> function invocation BEFORE (which STRICT essentially does),
>> I could abort it AFTER invocation (once I had detected
>> the NULL argument)
>
> Are you sure you understand what STRICT does? STRICT doesn't abort
> anything. STRICT means "if this function gets called with any NULL
> arguments, the result is NULL". Since this is correct behaviour for the
> vast majority of functions, it's implemented as a flag rather than
> requiring each and every function to check.

Ah, I have misunderstood this!  I saw it as "if invoked with NULL,
don't invoke the function" -- which, I guess, is somewhat consistent
with your comment... the function isn't invoked, BUT 'NULL' IS
SUBSTITUTED FOR IT'S RETURN VALUE.

> Also, anything that calls a function must be prepared to handle a NULL
> return value. Any function can return NULL, even if only because it is
> declared strict and you passed a null argument...

So, even the functions that I am defining that ALWAYS return
particular types have to be treated AS IF they could return NULL?
(in the case you describe -- the opposite case that I have been
describing)

Hmmm... that might make things even easier!