There is a slight bug in this solution, it drops letters.
Using the above test data, the following list is generated:
1, 1.2, 2, 2.1.7, 2.2, 2.13, 3.4, 10.1, 10.1, 10.10
which dropped the letters from the section headings.
Here's my version: 
@sorted = 
    map {$_->[0], ", "}
    sort {$a->[0] <=> $b->[0]}
    map {[$_, pack ("N*", $_)]}
    
@unsorted;

[download]

it works the same way, but I substituted in a Schwartzian transform to cache the original value of the heading instead of unpacking it again later. According to some tests with Benchmark, it's about 40% faster than doing the unpack later.
Plus it keeps letters intact.

In reply to RE: RE: Re: Sorting on Section Numbers by jimt
in thread Sorting on Section Numbers by Zoogie

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