On 10 Jan, 21:47, Ed Jensen <[EMAIL PROTECTED]> wrote: > Bruno Desthuilliers <[EMAIL PROTECTED]> wrote: > > I fail to see how the existence of JIT compilers in some Java VM changes > > anything to the fact that both Java (by language specification) and > > CPython use the byte-code/VM scheme. > > While your answer was technically correct, by omitting pertinent > information, your answer lead readers to the wrong conclusion.
Indeed. A perusal of the Java VM architecture documents plus any discussions around dynamic language support (and there's a discussion group about that very topic) reveal a number of differences between the CPython VM and Sun's Java VM. Moreover, despite claims about the Sun VM only being one of many, it holds a fairly similar position to that of the CPython VM in its own part of the computing world, with adoption only likely to increase now that it's open source. (And many new adopters were quite possibly using stuff like gcj previously which, as many will already know, is a native code compiler for Java.) These days, I seriously doubt that anyone uses the term "interpreted" to mean "parses the source text and works out what to do, over and over again as the program runs". Instead, I imagine that the term typically suggests the presence of a virtual processor doing what all processors do: interpret instructions. It's just that when native code is produced, we look away from the process of interpretation done by the hardware and consider it as the plain "on the metal" execution of the code. Sure, Sun's Java VM may not remove such a virtual processor entirely from the overall execution of a program, and the output of gcj may include the invocation of lots of moderately expensive library calls, but in contrast with CPython, some sequences of instructions will not ultimately be interpreted by the virtual machine at run-time. All this said, there are options other than CPython, and I imagine that they will become even more interesting to mainstream Python users over the next months and years. Paul -- http://mail.python.org/mailman/listinfo/python-list
