This doesn't produce an error: 
my $fname = 'data.txt';

open FH, "<", $fname
    or die "Couldn't open $fname: $!";

while(FH) {
    print "hello\n";
}

[download]
Nor does this:

while(FH) {
    print "hello\n";
}

[download]

According to "Perl Best Practices", p. 65:

In Perl, any identifier that the compiler doesn't recognize as a subroutine (or as package name or filehandle or label or builtin function) is treated as an unquoted character string:

$greeting = Hello . World;
print $greeting, "\n";           #Prints: HelloWorld

[download]
I'm not sure why there are parentheses around "or package name or filehandle..." because the section is not about subroutines. And it should say, "...is treated as a string".

In reply to Re: Why is the error thrown from close(FH) when the error is the missing <> on while(FH)? by 7stud
in thread Why is the error thrown from close(FH) when the error is the missing <> on while(FH)? by techgrrl

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