3 attempts, the shortest weighing in at 77 characters(!), using japhys sort trick. I'm quite fond of the last two.

my @d=(1089,3,4,0,5,6,7,99,832,1087,831,1088,10000);
print "\nfirst try\n\n";
@ary= boo(@d);
print "@ary";
print "\n\nsecond try\n\n";
@ary=boo2(@d);
print "@ary";
print "\n\nthird try (stringify)\n\n";
$list=boo3(@d);
print $list;
sub boo {
#        1         2         3         4         5         6         7
+         8         9         A         B         C
#234567890123456789012345678901234567890123456789012345678901234567890
+1234567890123456789012345678901234567890123456789012345
@_=sort{$a-$b}@_;$a[0]=$_[0];map{$q=$_[$_-1];$_[$_]==$q+1||do{$a[-1].=
+"-$q";push@a,$_[$_]};$a[-2]=~s/(\d+)-\1/$1/}(1..$#_);@a
}

sub boo2 {
#        1         2         3         4         5         6         7
+         8
#234567890123456789012345678901234567890123456789012345678901234567890
+123456789012345678
$_=join$",sort{$a-$b}@_;while(/(\d+)/g){$e=$1+1;s/($1) $e/$1-$e/;s/-\d
++-/-/}split" "
}

sub boo3 {
# stringify
#        1         2         3         4         5         6         7
+       
#234567890123456789012345678901234567890123456789012345678901234567890
+1234567
$_=join$",sort{$a-$b}@_;while(/(\d+)/g){$e=$1+1;s/($1) $e/$1-$e/;s/-$1
+-/-/}$_
}
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