local cache={}
local function cload(callback)
local c=cache[callback]
if not c then
c=callback()
cache[callback]=c
end
return c
end

return function(proxy)
return
{
contents={read=proxy.get,write=proxy.set},
data={read=proxy.getData,write=proxy.setData},
checksum={read=proxy.getChecksum,size=function()return 8 end},
size={cload(proxy.getSize)},
dataSize={cload(proxy.getDataSize)},
label={write=proxy.setLabel,proxy.getLabel()},
makeReadonly={write=proxy.makeReadonly}
}
end