On Mon, Jun 16, 2003 at 11:19:21AM -0700, Daschbach, John L wrote:
>
> > > Add an extra variable and set that, like
> > >
> > > $exitloop = false;
> > > while(<FH> || $exitloop){
> >
> > What do you suppose happens to the input from <FH> in that line of code?
>
> It's in $_ as it always is.
Ah ha! No, it is not. It is discarded.
In the loop:
while(<FH> || $exitloop) {
}
the input read from <FH> is not assigned to $_, because the implicit
assignment only happens when the input operator is the only thing in the
conditional.
perldoc perlop:
Ordinarily you must assign the returned value to a vari-
able, but there is one situation where an automatic
assignment happens. If and only if the input symbol is
the only thing inside the conditional of a "while" state-
ment (even if disguised as a "for(;;)" loop), the value is
automatically assigned to the global variable $_, destroy-
ing whatever was there previously.
Ronald
