ah - i get it now.
thanks.
On Wed, Feb 1, 2012 at 3:05 PM, Jim Gibson <jimsgib...@gmail.com> wrote:
> On 2/1/12 Wed Feb 1, 2012 11:24 AM, "jbiskofski" <jbiskof...@gmail.com>
> scribbled:
>
> > Your comment about the open statement is OK. I guess it really comes down
> > to style. I was trying to write something clear that Brandon could
> improve
> > upon.
>
> It is not simply a matter of style. Because of operator precedence, the
> statement
>
> open my $RR, '<', 'nagios.dat' || die 'unable to open nagios.dat :(';
>
> will be parsed as
>
> open my $RR, '<', ('nagios.dat' || die 'unable to open nagios.dat :(');
>
> because the precedence of '||' is higher than that of ','. Because the
> scalar value 'nagios.dat' is always true, the above statement is equivalent
> to the following:
>
> open my $RR, '<', 'nagios.dat';
>
> In other words, the die will never get executed, regardless of the success
> or failure of the open. So you either need to place parentheses around the
> open arguments:
>
> open( my $RR, '<', 'nagios.dat') || die 'unable to open nagios.dat :(';
>
> or use the lower-precedent 'or' operator:
>
> open my $RR, '<', 'nagios.dat' or die 'unable to open nagios.dat :(';
>
> as Timothy has suggested.
>
> For operator precedence, see 'perldoc perlop'.
>
>
>
>
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