I have a function that takes a reference to hash as a parameter. This has has one element that's a reference to (multidimensional) array. Now, I tamper a lot with that array and the form $$hash{arraykey}[$i][$j] notation is a bit tiresome compares to $array[$i][$j], not to mention that other uses such as @{$$hash{arraykey}} can get pretty confusion. So, I figured, why not alias them? We have this local() function here just for that (amongst other things...), right? After some pretty confusing warnings, here's a testbed I used to track down the problem. It's not pruned enough to get to the core, but close enough, I suppose. 
%hap=(
    'foo' => "hip",
    'bar' => [ 2, "blah", ],
);

hum(\%hap);
print "$hap{foo} $hap{bar}[0] $hap{bar}[1]\n";


sub hum {
    local *hash=$_[0];
    local *array=$hash{bar};

    print "$hash{foo} $array[0] $array[1] / @array\n";
#   print "$hash{foo} @array\n";
    $hash{foo}="gaa";
    $array[1]=5;
}

[download]

Now, see the print lines in sub hum. On my perl 5.6.0, the form I just pasted works fine, whereas commenting the first print out and uncommenting the second gives 

In string, @array now must be written as \@array at ./test2.pl line 17, near "} @array"

Now, the only difference is that I use values inside that @array before using the @array itself. Did I get something about local() wrong here, or is that a genuine bug? And do you have any comments on how I should go on with aliasing @{$$_[0]{bar}} to @array ?

In reply to local() peculiarities by kaatunut

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