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To: "M. Warner Losh" <imp@bsdimp.com>
In-reply-to: Your message of "Sun, 28 Oct 2007 00:03:00 MDT."
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Date: Sun, 28 Oct 2007 00:43:09 -0700
From: Bakul Shah <bakul@bitblocks.com>
Message-Id: <20071028074310.233895B3E@mail.bitblocks.com>
Cc: bms@incunabulum.net, freebsd-arch@freebsd.org
Subject: Re: C++ in the kernel 
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> scripting languages, will never be in the kernel.  The old vmkernel.el
> joke will never happen either (although there's been rumors of an
> in-kernel compiled-lisp interprater floating around).  C++ support,
> driven by people's experience with OS X, will continue to be a highly
> desired feature.

Are you thinking of Bill Bland's Schemix for linux?

$ echo '(+ 1 2 3)' > /dev/schemix
$ cat /dev/schemix
6
$ echo '(define foo (kernel-lambda (char*) printk))' > /dev/schemix
$ echo '(foo blah blah blah)' >/dev/schemix
$ dmesg |tail -1
blah blah blah

Speaking of vmkernel.el do you know about Movitz (Commom
Lisp on bare metal)?

Of course, this has nothing to do with why people want C++ in kernel!

>              However, having C++ support would allow the extreme
> FreeBSD users to suffer or benefit from C++ in their kernels without
> having to reinvent the base wheel.  I think the arguments are strong
> enough for this, but not so strong as to accept it into the base at
> this time without some compelling proof that it can be done, in
> FreeBSD, without extreme pain.

It will be the proverbial camel's nose in the tent.  A subset
of C++ is attractive for kernel work but it will be hard to
hold the line at that.  How long before people clamor for
things like

    TailQ<Mount> mount_list;
    TailQ<Mount>::iterator mp;

    for(mp = mount_list.begin(); mp != mount_list.end(); mp+) {
	...
    }