Ever since perl 5.004 the code:

while ($line = <FH>)

has an implicit defined check, so that it's actually:

while (defined($line = <FH>))

This was because, prior to this, that code would emit a warning; it was a common enough desire that perl was simply modified to accept it as intended.

Also, while it is possible for a line to have "0" on it, with no newline, it isn't possible for <FH> to return "" unless it's tied.

In reply to Re^2: Using null filehandle by Somni
in thread Using null filehandle by digger

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