I said that this was how I read that, and parens do matter here:

$ cat test.pl
#!/pro/bin/perl

use strict;
use warnings;

my $file = "/tmp/test20.pl";

-e   $file      and print "$file EXISTS!\n";
print "$0 \n";
- e  $file      and print "$file WILD!\n";
$ perl test.pl
test.pl
Can't call method "e" without a package or object reference at test.pl
+ line 10.
$
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versus

$ cat test.pl
#!/pro/bin/perl

use strict;
use warnings;

my $file = "/tmp/test20.pl";

-e   $file      and print "$file EXISTS!\n";
print "$0 \n";
- e ($file)     and print "$file WILD!\n";
$ perl test.pl
test.pl
Undefined subroutine &main::e called at test.pl line 10.
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