On Oct 9, 2:09 am, "." <[EMAIL PROTECTED]> wrote: > On Tue, 09 Oct 2007 05:15:49 +0000, gnuist006 wrote:
> > (3) Is it present in python and java ? > > Certainly not Java, I dunno about Python. I've never seen someone use > them in Python, but the pythonistas seem to want to add everything but a > decent lambda to their language so I wouldn't be surprised if someone had > added a call/cc. Ruby has it. > Continuations exist in all computer languages---actually, in anything that executes code. The continuation is simply "what will happen for the rest of the program execution." What might or might not exist is an explicit linguistic mechanism to examine it, refer to the continuation as a function, or to save it for later use. > > (4) Its implementation in assembly. for example in the manner that > > pointer fundamentally arises from indirect addressing and nothing new. > > So how do you juggle PC to do it. > The continuation is typically present in the stack, which contains all the control-flow information needed to continue program execution from this point. (I.e., the function call mechanism includes a step saving the location of the instruction to execute when the function call is complete, and any registers that it will restore after the function returns because the function call might destroy them.) How you save that continuation for later, possibly repeated, use from a different location in the program is a different question. -- http://mail.python.org/mailman/listinfo/python-list