SmallInteger and machine word size

> Hello,
>
> I want to use integer values to pass them over a binary data stream.
> And for this i need to encode a smallinteger value into bytearray
> (endianess not matters).
> Is there any way how to do it in platform independent way?
> Lets say, if we have a SmallInteger>>asByteArray
> then it should return an array of 4 bytes on 32 bit architecture and 8
> bytes on 64 bits.
>
> Or maybe, as variant, can i convert somehow Smallinteger to Big one,
> without make it auto-converted back to SmallInteger?

>
> On Feb 19, 2008, at 14:13 , Igor Stasenko wrote:
>
> > Hello,
> >
> > I want to use integer values to pass them over a binary data stream.
> > And for this i need to encode a smallinteger value into bytearray
> > (endianess not matters).
> > Is there any way how to do it in platform independent way?
> > Lets say, if we have a SmallInteger>>asByteArray
> > then it should return an array of 4 bytes on 32 bit architecture and 8
> > bytes on 64 bits.
> >
> > Or maybe, as variant, can i convert somehow Smallinteger to Big one,
> > without make it auto-converted back to SmallInteger?
>
> What do you need this for? Why do you care if it is a SmallInteger?
> Doesn't #int32: do what you want?
>

> On Tue, 19 Feb 2008 14:13:09 +0100, Igor Stasenko wrote:
>
> > Hello,
> >
> > I want to use integer values to pass them over a binary data stream.
> > And for this i need to encode a smallinteger value into bytearray
> > (endianess not matters).
> > Is there any way how to do it in platform independent way?
>
> These are the requirements addressed by class InterpreterSimulator (and
> its superclass and subclasses) when it saves+restores its .image; you have
> the solutions in the VMMaker package.
>
> /Klaus

> On 19/02/2008, Klaus D. Witzel wrote:
>> On Tue, 19 Feb 2008 14:13:09 +0100, Igor Stasenko wrote:
>>
>> > Hello,
>> >
>> > I want to use integer values to pass them over a binary data stream.
>> > And for this i need to encode a smallinteger value into bytearray
>> > (endianess not matters).
>> > Is there any way how to do it in platform independent way?
>>
>> These are the requirements addressed by class InterpreterSimulator (and
>> its superclass and subclasses) when it saves+restores its .image; you  
>> have
>> the solutions in the VMMaker package.
>>
>> /Klaus
>
> This is true, but not helps to write any code not related to VMMaker.
> It's a generic problem:
>  suppose you want to pass ANY integer value to binary stream.

> Since smalltalkers care little, how integers are stored, i implemented
> 2 methods for encoding and decoding integer values from bytearray.
>
> The only limitation of my method, is that it can't encode too large
> integers (with number of bytes > 127 to store it).
>
> encodeInt: anInteger
> | length bytes |
>
> length := anInteger digitLength.
> bytes := ByteArray new: length + 1.
> bytes at: 1 put: ( (length bitShift: 1) + (anInteger < 0 ifTrue: [1]
> ifFalse: [0]) ).
>
> 1 to: length do: [:i |
> bytes at: i+1 put: (anInteger digitAt: i)
> ].
>
> ^ bytes
> ----
> decodeInt: aBytes offset: index
> | neg result length |
>
> length := aBytes at: index.
> neg := (length bitAnd: 1) = 1.
> length := length bitShift: -1.
> result := Integer new: length neg: neg.
> 1 to: length do: [:i | result digitAt: i put: (aBytes at: index + i) ].
>
> ^ result
>

> On Tue, 19 Feb 2008 15:42:07 +0100, Igor Stasenko wrote:
>
> > On 19/02/2008, Klaus D. Witzel wrote:
> >> On Tue, 19 Feb 2008 14:13:09 +0100, Igor Stasenko wrote:
> >>
> >> > Hello,
> >> >
> >> > I want to use integer values to pass them over a binary data stream.
> >> > And for this i need to encode a smallinteger value into bytearray
> >> > (endianess not matters).
> >> > Is there any way how to do it in platform independent way?
> >>
> >> These are the requirements addressed by class InterpreterSimulator (and
> >> its superclass and subclasses) when it saves+restores its .image; you
> >> have
> >> the solutions in the VMMaker package.
> >>
> >> /Klaus
> >
> > This is true, but not helps to write any code not related to VMMaker.
> > It's a generic problem:
> >  suppose you want to pass ANY integer value to binary stream.
>
> Then forget about C-land and enter beautiful Squeak-land :) The next thing
> you might also want to put into your ByteArray is perhaps a String, so
> here's the data-independent solution:
>
>   | byteStream dataStream |
>   byteStream := (ByteArray new: 10) writeStream.
>   dataStream := DataStream on: byteStream.
>   dataStream nextPut: SmallInteger maxVal + 1; close.
>   "close not really needed for streams on arrays"
>   byteStream contents inspect.
>   dataStream := DataStream on: byteStream contents readStream.
>   dataStream next inspect
>
> No knowledge about digitLength, nor about digitAt* etc (which is
> *not*necessary* for you but for implementors of the Number hierarchy
> anyways).
>