One of the things I detest about fixed-length field parsers is that they require me to count characters (Either field width, or , worse, Start and end columns).

What I'd like to see is something that lets me paste-in a data sample, and mark field boundries using special characters, then allows me to name them. Something like:

# Sample Data ----
# FirstName       Lastname     YearBorn    LastHaircutDate

# I'd like to specify the above as:
my $fields=
" [irstName       ][astname     ][earBorn   ][astHaircutDate ]";
my @fieldnames=qw( FirstName       Lastname     YearBorn    LastHaircu
+tDate);
#Alternatively, allow optional TYPE specification with mixed hashrefs 
+and strings:
my @fieldnames=( 'FirstName',       'Lastname',     {name=>'YearBorn',
+type='integer'},  {name='LastHaircutDate',type='date'});
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I also like the idea of specifying the info using XML.