The following code was an answer posted to a query a long time back on how to sort a text file that had 5 columns of numbers and the user wanted to sort based on 2nd column. I don't understand the solution and was hoping someone could explain it. 

use strict;
use File::Slurp qw(read_file);

print map      { $_->[1] }
      sort     { $a->[0] <=> $b->[0] }
      map      { [(split /\s+/)[1], $_] }
      read_file( $ARGV[0] );

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In reply to how does these map statements work by martin_100

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