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Comment by edward | Hacker News Reader

This is copied from Perl. See http://stackoverflow.com/questions/161872/hidden-features-of...

  my @lines = <DATA>;
  for (@lines) {
      print if /bad/;
  }
  
  __DATA__
  some good data
  some bad data
  more good data 
  more good data

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And widely used in the perl world. It's a good idea for a lot of simple programs.

Agreed, this is not a "hidden feature."

Which had copied this (including the "DATA" name) from good old BASIC:

     10 DATA 1,2,3,4,5,6,7,8,9
     20 FOR I=1 TO 9
     30 READ A(I)
     40 NEXT I

As quite a good few things in ruby are. Having never really learned perl, I keep discovering them anew in ruby first :-)

And in Perl there are also: __FILE__ , __LINE__ , __PACKAGE__ , __SUB__ & __END__

These are called Special Literals - http://perldoc.perl.org/perldata.html#Special-Literals

Ruby also has __FILE__ and __LINE__.

Yep. And in Perl6 these were changed to:

    __LINE__            $?LINE
    __FILE__            $?FILE
    __PACKAGE__         $?PACKAGE
    __END__             =begin END
    __DATA__            =begin DATA

ref: http://feather.perl6.nl/syn/S02.html#Double-underscore_forms

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