it's no doubt something really ridiculous I'm doing wrong.

Dunno! Your code and your hypers file produce the apparently desired result on my machine: 

C:\test>type junk12.pl
#!c:/perl/bin/perl
use strict;

open (HYPERS, "< hypers.txt");
my @hypers = <HYPERS>;
chomp @hypers;
print "Hypers array: @hypers\n";
foreach my $line(@hypers){
$line =~ /([0-9a-f]+):([0-9a-f]+)$/i
    and my @range = map sprintf( '%x,',$_ ), eval "0x$1 .. 0x$2";;
    print @range;;

}
C:\test>type hypers.txt
293F:2946

C:\test>junk12
Hypers array: 293F:2946
293f,2940,2941,2942,2943,2944,2945,2946,
C:\test>

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The start of some sanity?

In reply to Re^3: Extracting full digits from a range by BrowserUk
in thread Extracting full digits from a range by smw6181

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