I don't understand why the following dies on the last line. 

#!/usr/bin/perl

use strict;
use warnings;

my($bad)='/this/path/does/not/exist';
die "$bad exists, but must not\n" if -f $bad;

my($yes1)=(defined $bad and -f $bad); #2nd parens seem unnecessary,
die "yes1=$yes1\n" if $yes1;          #but does not die here; good

my($yes2)=defined $bad and -f $bad;   #2nd parens removed,
die "yes2=$yes2\n" if $yes2;          #but dies here; why?

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The parentheses on the left-hand side of the my statement for both $yes1 and $yes2 should impose list context on the right-hand side. So I'd expect the parentheses added for $yes1 to have no effect. Also, I didn't think the two operators used here, defined and -f, changed behavior between scalar and list context. Also, I'd expect the low-precedence and to keep the defined and the -f separated from each other.

This is on Linux with Perl 5.10.1, which I can't control. Thanks.

Jim

In reply to Surprising Precedence/Context by williams

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