According to the perlsyn (Perl Syntax) man page ...

  while (<FH>) {

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... is equivalent to ...

  while (defined($_ = <FH>)) {

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Conventional Perl wisdom has it that if you're not using $_, but assigning to a named variable ...

  while (my $line = <FH>) {

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... then you should write it like this ... 

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

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The reason being, you only want the loop to terminate at the end of file (<FH> will return undef) and not when you read a line that happens to evaluate to false.

My question is: Assuming $/ still contains the default value, is it possible to read a line which evaluates to false?

A quick experiment shows that the string "0" is false, but "0\n" is true. Can anyone give a string with a trailing newline that evaluates to false in a boolean context?

And, if changing $/ does make it possible, what would I have to change it to?

In reply to Can you read a false value from a file? by grantm

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