Re^4: Emulating 'sort' command through a Perl

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Re^5: Emulating 'sort' command through a Perl by Marshall (Canon) on Oct 31, 2009 at 10:02 UTC
You are most welcome! On another point...white space is the easiest thing that you can do to enhance code readability and understandability. Consider this re-formatted code with just white space added... Now it is clear that the "map{}sort{}map{}<>" "stack" feeds the "for" loop. The "for" is iterating on the list provided by the map { $_->[0] } which is the end result of the 4 lines in this map{}sort{}map{}<> "stack" (which is actually just one line). When that whole thing is nicely indented, it is easier to see. Human eyeballs work best vertically, not diagonally. `for ( map { $_->[0] } sort { $a->[1] cmp $b->[1] } map { [$_, (split)[$column_number] ] } <> ) { print unless $_ eq $prev; $prev = $_; }` [download] This "for" statement is the same as: `for(map{$_->[0]}sort{$a->[1]cmp$b->[1]}map{[$_,(split)[$column_number]]}<>)` what do you think is easier to read?	[reply] [d/l] [select]

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Re^5: Emulating 'sort' command through a Perl
by Marshall (Canon) on Oct 31, 2009 at 10:02 UTC

Consider this re-formatted code with just white space added... Now it is clear that the "map{}sort{}map{}<>" "stack" feeds the "for" loop. The "for" is iterating on the list provided by the map { $_->[0] } which is the end result of the 4 lines in this map{}sort{}map{}<> "stack" (which is actually just one line). When that whole thing is nicely indented, it is easier to see. Human eyeballs work best vertically, not diagonally.

for  (
         map  { $_->[0] }
         sort { $a->[1] cmp $b->[1] }
         map  { [$_, (split)[$column_number] ] }
         <>
     )
{
   print unless $_ eq $prev;
   $prev = $_;
}
[download]

for(map{$_->[0]}sort{$a->[1]cmp$b->[1]}map{[$_,(split)[$column_number]]}<>)

[reply]
[d/l]
[select]