my @accumulator;
foreach my $item ( split ',', $string ) {
    my @elems = split '=', $item;
    if ( @elems == 1 ) {
        push @accumulator, "fn($item)";
    }
    else {
        if ( $elems[1].substr(0,1) eq '#' ) {
            push @accumulator, $elems[0] . '=>fn(' . $elems[1] . ')';
        }
        else {
            push @accumulator, "$elems[0]=>$elems[1]";
        }
    }
}
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