rick@digitaldreams3d.com informed me that Squeak3.9a-7021.image won't let him export a jpeg image of a morphic. It fails in

JPEGReadWriter2(Object)>>error: Receiver: a JPEGReadWriter2 Arguments and temporary variables: aString: 'a primitive has failed' Receiver's instance variables: stream: MultiByteFileStream: '/Users/rick/Desktop/Squeak3.9a-7021/ System Browse...etc...

JPEGReadWriter2(Object)>>primitiveFailed Receiver: a JPEGReadWriter2 Arguments and temporary variables:

Receiver's instance variables: stream: MultiByteFileStream: '/Users/rick/Desktop/Squeak3.9a-7021/ System Browse...etc...

JPEGReadWriter2>>primJPEGWriteImage:onByteArray:form:quality:progressive JPEG:errorMgr: Receiver: a JPEGReadWriter2 Arguments and temporary variables: aJPEGCompressStruct: a ByteArray(0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 ...etc... destination: a ByteArray(0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 ...etc... form: Form(692x525x32) quality: -1 progressiveFlag: false aJPEGErrorMgr2Struct: a ByteArray(0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0...etc... Receiver's instance variables: stream: MultiByteFileStream: '/Users/rick/Desktop/Squeak3.9a-7021/ System Browse...etc...

JPEGReadWriter2>>nextPutImage:quality:progressiveJPEG: Receiver: a JPEGReadWriter2 Arguments and temporary variables: aForm: Form(692x525x32) quality: -1 progressiveFlag: false sourceForm: Form(692x525x32) jpegCompressStruct: a ByteArray(0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0...etc... jpegErrorMgr2Struct: a ByteArray(0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 ...etc... buffer: a ByteArray(0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0...etc... byteCount: nil Receiver's instance variables: stream: MultiByteFileStream: '/Users/rick/Desktop/Squeak3.9a-7021/ System Browse...etc...

However in looking at the code when the primitive attempts to resolve the Form argument it calls interpreterProxy->success(interpreterProxy->isKindOf (interpreterProxy->stackValue(3), "Form")); but when you wander down the isKindOf() logic into sqInt classNameOfIs (sqInt aClass, char * className)

name = longAt((aClass + BaseHeaderSize) + (6 << ShiftForWord)); if (!(((name & 1) == 0) && (((((usqInt) (longAt(name))) >> 8) & 15)

= 8))) {

return 0; }

It returns 0 at this point, which is the check to see if the class name in slot 6 is a string. It is not...

Now wasn't there something about traits altering the class description and shifting things so that perhaps the class name isn't what you expect anymore. I'll note I tested this with a 7006 3.9a image and had the same problem.

-- ======================================================================== === John M. McIntosh johnmci@smalltalkconsulting.com 1-800-477-2659 Corporate Smalltalk Consulting Ltd. http://www.smalltalkconsulting.com ======================================================================== ===