Hello,
I was advised by a member of Perl Guru to ask at Perl Monks whether it would be possible or not to perform a type of sort i'm trying to achieve. I would rather not perform this sort outside of the sort block, as I will later choose the type of sort from a hash lookup of subroutine refs.
Here is my code: 
foreach my $colour ( 
    sort { 
        if ($products{'Cat'}{'Pro'}{$a}{'Qua'} <= 0) {return 1;} 
        elsif ($products{'Cat'}{'Pro'}{$b}{'Qua'} <= 0) {return -1;} 
    } 
    sort {$a <=> $b || $a cmp $b} 
    keys %{$products{'Cat'}{'Pro'}} 
) {

[download]

Here is its output (example): 
Colour                    Quantity

70 (Grey brown mix)       3
72 (Green mix)            10    
74 (Fuschia mix)          8
76 (Mauve mix)            11
77 (Blue mix)             6    
90 (Beige pink mix)       12    
91 (Peach cream mix)      8     
92 (Silver cream mix)     10    
93 (Beige blue mix)       9    
78 (Black white mix)      0    
75 (Red mix)              0
73 (Aqua mix)             0
71 (Beige mix)            0

[download]

As you can see, colours with a quantity of more than 0 are displayed above those with a quantity of 0. However, each group must then be sorted in alphabetical order, and although close, products with a quantity of 0 are being undesirably sorted in reverse.
I can see why the code doesn't work as desired, but i'm unable see a way to adjust it to suit my full requirements.
Is it possible without breaking out of the sort block?
Chris

In reply to Complex conditional sort by Zhris

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