ORLY? 

while( <DATA> ) {
  print defined $_ ? "Defined! " : "Undefined! ", $_;
}
__END__
Please to be not
misinforming people with
incorrect information.

[download]

The discussion on looping constructs in perlsyn clearly explains this construct. Perhaps you should try reading it?

Addendum: Not to mention the docs for $_ as well.

The cake is a lie.
The cake is a lie.
The cake is a lie.

In reply to Re^2: about split by Fletch
in thread about split by halfcountplus

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