From: mike@... (Mike Stok)
Date: 2003-12-14T04:57:07+09:00
Subject: Re: .unpack("B*")

In article <brfo5f$fun$1@news.rz.uni-karlsruhe.de>,
Boris \"BXS\" Schulz <bxs@hadiko.de> wrote:
>Hi,
>
>I have a problem with "unpack".
>When I try to unpack a string, I can easily adress the individual chars 
>via the array.
>But when I try to extract the binary values of a string, this does not 
>work anymore. I can neither adress individual binary digits, nor the 8 
>bits corresponding to a char.
>Is this a feature or a bug ? And what can I do to adress the bits 
>individually ? Further, how do I get the binary values of an integer ?
>
>char = "ABCDE"
>myint = char.unpack("B*")
>puts myint >> 0100000101000010010000110100010001000101
>puts myint[3] >> nil

unpack returns an Array:

irb --simple-prompt
>> char = "ABCDE"
=> "ABCDE"
>> myint = char.unpack("B*")
=> ["0100000101000010010000110100010001000101"]
>> puts myint[0][3 .. 3]
0
=> nil
>> puts myint[0][3]
48
=> nil
>> myint = *char.unpack("B*")
=> "0100000101000010010000110100010001000101"

Hope this helps,

Mike

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