If the file is like 7, 10\n, maybe 
open(my $filehandle, '<', $filename)
  or die "error opening $filename: $!";

my @pairs = 
  sort { $$a[0] <=> $$b[1] }
  map { chomp; [ split /\s*,\s*/ ] }
  grep { /\S/ } # skip empty lines
  <$filehandle>;

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In reply to Re: beginner - ordering tuples by Anonymous Monk
in thread beginner - ordering tuples by Anonymous Monk

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