in reply to Re^3: Writing hashes as records to a CSV file (joining keys with slices)
in thread Writing hashes as records to a CSV file

And for the spirit of TIMTOWTDI: 
sub map_direct {
    my %H = (map %$_, @$AoH);
    return keys %H
}

sub map_keys {
    my %H;
    @H{map keys %$_, @$AoH} = ();
    return keys %H
}

[download]

map{substr$_->[0],$_->[1]||0,1}[\*||{},3],[[]],[ref qr-1,-,-1],[{}],[sub{}^*ARGV,3]

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Re^5: Writing hashes as records to a CSV file (joining keys with slices)
by Tux (Canon) on Dec 10, 2021 at 08:03 UTC
[reply]
[d/l]
[select]

In Section Seekers of Perl Wisdom