I'm trying to get my head around some (what I think are) basic bitfield manipulations using either vec() or un/pack... but I've not used these functions much and I'm going around in circles.

I have a single 8-bit byte where each bit represents whether a directly-mapped item is 'included' or not. An example: 

$actions = " ABCDEFG";
$item = 0x37;  # ...or 00110111b
$newitem = &SomeMagic($item); # ...giving "  BC EFG"

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I would think it's something pretty simple but I haven't been able to nut it out or find anything like it in any of my books or any net searches.

Any suggestions?

Thanks.

In reply to Decoding Mapped Bitfields by ozboomer

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