Monks,

I am writing some code that takes a number of pieces of data and packages them up into one large chunk. I am using pack to do this, and it works fine in most cases. E.g., 

my $eight_bit_piece = 255;
my $other_eight_bit_piece = 255;
my $sixteen_bit_piece = 8;

my $packaged_data = pack("CCn",
    $eight_bit_piece,
    $other_eight_bit_piece,
    $sixteen_bit_piece);
# Gives me 11111111 11111111 0000000000001000 as desired

[download]

However, I don't know what to do when my individual pieces of data don't divide cleanly into 8-bit chunks. For example, I want to assemble a 16-bit word from two six-bit and one four-bit chunks: 

my $piece_one_six_bits = 12;   # 001100
my $piece_two_six_bits = 12;   # 001100
my $piece_three_four_bits = 5; #   0101

# What now?

[download]

I have come up with a solution... 

my $packaged_data = pack("n",
                          $piece_one_six_bits << (6 + 4)
                        | $piece_two_six_bits << 4
                        | $piece_three_four_bits
                        );

[download]
... but it doesn't feel right. I am trying to avoid bitwise operations. Isn't this work pack should be able to do? Can anybody point me in the right direction with this?

Thanks in advance for your help.

In reply to Using pack with data of odd lengths by crashtest

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