It seems like that problem is needlessly being complicated by conflating key extraction and sorting. (This was an issue that was discussed on perl6-language about the current sort operator — how do we make it possible to isolate the extraction code from the actual sort order, which should then be possible to request declaratively?)

sub order_of_sorted { my ( @num, @suff ); for( @_ ) { m/ \A (\d+) \. (.*) /x or die "malformed data"; push @num, $1; push @suff, $2; } sort { $num[$a] <=> $num[$b] or $suff[$a] cmp $suff[$b] } 0 .. $#_ +; } for my $outer ( ( values %hash )[ order_of_sorted keys %hash ] ) { for my $inner ( ( values %$outer )[ order_of_sorted keys %$outer ] + ) { # ... } }

If you want to store the data rather than output it, you can transform the nested for-loops to an equivalent chain of maps (but note that that doesn't make it an ST).

I know which version I'd prefer to maintain, even though this is probably slower than your GRT.

Update: the following, which I originally wrote, is obviously wrong:

for my $inner ( ( values %$outer )[ order_of_sorted keys %$inner ] +) { # ^^^^^^^ Correct. ^^^^^^^ Oo +ps.

Makeshifts last the longest.


In reply to Re^3: To use a module...or not. by Aristotle
in thread To use a module...or not. by BrowserUk

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