From: Uday S Reddy <u.s.reddy@cs.bham.ac.uk>
To: emacs-devel@gnu.org
Subject: Re: e and pi
Date: Sat, 18 Sep 2010 22:37:02 +0100 [thread overview]
Message-ID: <i73be2$6ut$1@dough.gmane.org> (raw)
In-Reply-To: <87ocbux3y9.fsf@stupidchicken.com>
On 9/18/2010 8:10 PM, Chong Yidong wrote:
> You came up with this
> example:
>
> (defun make-inc (e)
> (lambda (m) (+ e m)))
>
> (let ((f (make-inc 3)))
> (funcall f 5))
>
> I agree that static scoping is much better in this example. But we
> could fix this simply by imposing static scope on function arguments.
> So, is there an equivalent scenario in which the proposed change to
> `let' is clearly desireable?
Consider this:
(defvar funny nil)
(let ((e 25))
(setq funny (lambda (m) (+ e m))))
Now, (funcall funny 2) should return 27. Instead, with dynamic binding, it
returns 4.7182...
The point is not whether `e' is being bound in a let or a defun. Rather, the
point is that we should be able to use a variable like `e' as a free variable
in a closure. We can do so only if it is governed by lexical binding.
Cheers,
Uday
next prev parent reply other threads:[~2010-09-18 21:37 UTC|newest]
Thread overview: 61+ messages / expand[flat|nested] mbox.gz Atom feed top
2010-09-16 13:25 e and pi Stefan Monnier
2010-09-16 13:44 ` Deniz Dogan
2010-09-16 15:37 ` Stefan Monnier
2010-09-16 13:47 ` Leo
2010-09-16 15:39 ` Stefan Monnier
2010-09-16 14:27 ` Helmut Eller
2010-09-16 15:44 ` Stefan Monnier
2010-09-16 18:52 ` Helmut Eller
2010-09-16 14:44 ` Jason Rumney
2010-09-16 22:54 ` Chong Yidong
2010-09-17 0:04 ` Deniz Dogan
2010-09-17 0:14 ` Wojciech Meyer
2010-09-17 7:00 ` David Kastrup
2010-09-17 8:09 ` Simon Leinen
2010-09-17 8:15 ` David Kastrup
2010-09-17 9:06 ` Stephen J. Turnbull
2010-09-17 9:21 ` David Kastrup
2010-09-17 9:47 ` Helmut Eller
2010-09-17 15:11 ` Stefan Monnier
2010-09-17 15:22 ` Lars Magne Ingebrigtsen
2010-09-17 15:56 ` Helmut Eller
2010-09-17 22:13 ` Stefan Monnier
2010-09-17 15:44 ` Wojciech Meyer
2010-09-17 15:50 ` Chong Yidong
2010-09-17 16:06 ` Wojciech Meyer
2010-09-17 16:18 ` Helmut Eller
2010-09-17 16:45 ` Glenn Morris
2010-09-17 17:14 ` Glenn Morris
2010-09-18 10:01 ` Eli Zaretskii
2010-09-18 10:21 ` Helmut Eller
2010-09-18 11:07 ` Eli Zaretskii
2010-09-18 11:26 ` Helmut Eller
2010-09-18 10:50 ` David Kastrup
2010-09-18 11:09 ` Eli Zaretskii
2010-09-18 14:27 ` Stephen J. Turnbull
2010-09-18 14:32 ` Andreas Schwab
2010-09-18 15:11 ` Drew Adams
2010-09-17 22:17 ` Stefan Monnier
2010-09-18 1:10 ` Chong Yidong
2010-09-18 8:30 ` Stefan Monnier
2010-09-18 19:10 ` Chong Yidong
2010-09-18 21:37 ` Uday S Reddy [this message]
2010-09-19 0:57 ` Drew Adams
2010-09-18 13:43 ` Juanma Barranquero
2010-09-18 14:53 ` Stefan Monnier
2010-09-18 15:01 ` Lars Magne Ingebrigtsen
2010-09-18 16:00 ` Stefan Monnier
2010-09-19 10:07 ` Juanma Barranquero
2010-09-17 16:14 ` Drew Adams
2010-09-18 15:12 ` tomas
2010-09-18 17:52 ` David Kastrup
2010-09-19 19:13 ` tomas
2010-09-17 23:35 ` Uday S Reddy
2010-09-17 16:55 ` Sam Steingold
2010-09-17 22:16 ` Stefan Monnier
2010-09-17 22:55 ` Drew Adams
-- strict thread matches above, loose matches on Subject: below --
2010-09-17 4:20 MON KEY
2010-09-18 5:58 MON KEY
2010-09-18 14:50 ` Stefan Monnier
2010-09-19 2:03 ` MON KEY
2010-09-18 16:07 ` David De La Harpe Golden
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