Nathan Wiger wrote:
>
> undef null
> ------------------------ ------------------------
> $a = undef; $a = null;
> $b = 1; $b = 1;
> $c = $a + b; $c = $a + $b;
> $c is 1 $c is null
Uh, this is a difference in the implementations of the '+'
operator, not the data value undef/null.
Operators that treat undef the way SQL treats null are
trivial to implement.
> The keyword C<null> means that a value is B<known to be unknown>.
Maybe in your head; not in perl (the implementation).
--
John Porter
We're building the house of the future together.
- Re: RFC 263 (v1) Add null() keyword and ... Philip Newton
- Re: RFC 263 (v1) Add null() keyword and ... Glenn Linderman
- Re: RFC 263 (v1) Add null() keyword and ... Russ Allbery
- Re: RFC 263 (v1) Add null() keyword and ... Glenn Linderman
- Re: RFC 263 (v1) Add null() keyword and ... Russ Allbery
- Re: RFC 263 (v1) Add null() keyword and ... Glenn Linderman
- Re: RFC 263 (v1) Add null() keyword and ... John Porter
- Re: RFC 263 (v1) Add null() keyword and ... Russ Allbery
- Re: RFC 263 (v1) Add null() keyword and ... Glenn Linderman
- Re: RFC 263 (v1) Add null() keyword and fundamen... Paris Sinclair
- Re: RFC 263 (v1) Add null() keyword and fundamental data ... John Porter
- Re: RFC 263 (v1) Add null() keyword and fundamental ... Glenn Linderman
- Re: RFC 263 (v1) Add null() keyword and fundamen... Tom Christiansen
- Re: RFC 263 (v1) Add null() keyword and fund... iain truskett
- Re: RFC 263 (v1) Add null() keyword and ... Tom Christiansen
- Re: RFC 263 (v1) Add null() keyword and ... iain truskett
- Re: RFC 263 (v1) Add null() keyword and fund... Glenn Linderman
- Re: RFC 263 (v1) Add null() keyword and ... Tom Christiansen
- Re: RFC 263 (v1) Add null() keyword and ... Damien Neil
- Re: RFC 263 (v1) Add null() keyword and fundamen... Russ Allbery
- Re: RFC 263 (v1) Add null() keyword and fund... Graham Barr
