Hi Rolf, this is what I needed... having an older perl-version,I used for my $key (@keys) { $href =  $href->{$key} = {} unless defined $href->{$key};} is this notation {} having a specific usage or name ? Anyway, many thanks for the suggestion !!!

In reply to Re^4: define a hash-value, using hash-ref and a list of keys by janssene
in thread define a hash-value, using hash-ref and a list of keys by janssene

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