Re: Numeric sorting WITHOUT <=>

[roboticus]

Just look at the definition of the <=> operator, and you should be able to code it up easily: $a <=> $b is negative when $a should precede $b, positive if $a should follow $b, and zero if $a and $b could be the same position. So if you're sorting numbers, you could just use $a - $b, as it returns appropriate values. Using $b - $a would sort in reverse:

$ cat ex_sort_odd.pl 
#!/usr/bin/perl
use strict;
use warnings;

my @a;
push @a, int(100*rand) for 1 .. 10;
print "LIST: ", join(" ", @a), "\n";

my @b = sort { $a - $b } @a;
print "ASC:  ", join(" ", @b), "\n";

@b = sort { $b - $a } @a;
print "DESC: ", join(" ", @b), "\n";

$ perl ex_sort_odd.pl
LIST: 27 78 66 70 19 37 48 82 67 90
ASC:  19 27 37 48 66 67 70 78 82 90
DESC: 90 82 78 70 67 66 48 37 27 19

...roboticus

When your only tool is a hammer, all problems look like your thumb.