holli and wfsp, great answers. Now, I'd like to make this snippet of code more general by turning the delimiter into a variable. But doing so doesn't work (I'm struggling to understand regular expressions). 
my $delim = '|';
my $line = "a||c|\t|  |d||e";
my @fields = split(/\\$delim/, $line);

# output
# null fields: 0
# at field:

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In reply to Re^3: identifying null fields in bar delimited records by lupey
in thread identifying null fields in bar delimited records by jjohhn

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