On 07/10/2012 05:03 PM, Matthew Flatt wrote:
At Tue, 10 Jul 2012 10:51:57 -0400, Eli Barzilay wrote:
20 minutes ago, Marijn wrote:
It seems to me that both these results cannot be correct
simultaneously, but I'll await the experts' opinion on that.
This does look weird:
#lang racket
Hi!
Stefan Israelsson Tampe stefan.ita...@gmail.com skribis:
| It’s true that it’s annoying that the wrong binding is silently used.
| Do you think it’s common enough to justify new syntax?
Yes this highlights a comon problem when implementing racket match with #`.
Sure, but it’s not
I did miss something when trying in racket, it's a psyntax bug!
Look!
racket:
(define-for-syntax (f x) #`(let ((x 1)) #,x))
(define-syntax (g x) (syntax-case x ()((_ y) #`(let ((x y)) #,(f #'x
)
(g 4)
4
In guile,
scheme@(guile-user) (define (f x) #`(let ((x 1)) #,x))
scheme@(guile-user)
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On 10-07-12 15:35, Stefan Israelsson Tampe wrote:
I did miss something when trying in racket, it's a psyntax bug!
I'm glad you're finally looking harder at the Racket behavior.
racket: (define-for-syntax (f x) #`(let ((x 1)) #,x))
(define-syntax
20 minutes ago, Marijn wrote:
It seems to me that both these results cannot be correct
simultaneously, but I'll await the experts' opinion on that.
This does look weird:
#lang racket
(define-for-syntax (f stx) #`(let ([x 1]) #,stx))
(define-syntax (m stx)
(with-syntax ([zz (f
Hi,
Stefan Israelsson Tampe stefan.ita...@gmail.com skribis:
racket:
(define-for-syntax (f x) #`(let ((x 1)) #,x))
(define-syntax (g x) (syntax-case x ()((_ y) #`(let ((x y)) #,(f #'x
)
(g 4)
4
In guile,
scheme@(guile-user) (define (f x) #`(let ((x 1)) #,x))
scheme@(guile-user)
Hi,
Matthew Flatt mfl...@cs.utah.edu skribis:
It's natural --- but not correct --- to think that #` is responsible
for hygiene, in which case `(f #'x)' should keep the given `x' separate
from the `let'-bound `x' in the result.
[...]
If you change the example to
#lang racket
samth made a pointer to
http://srfi.schemers.org/srfi-72/srfi-72.html
It does not look like guile racket etc. have implemented this yet.
Am I wrong?
This is precisely what I'm after!
On Tue, Jul 10, 2012 at 5:26 PM, Ludovic Courtès l...@gnu.org wrote:
Hi,
Matthew Flatt mfl...@cs.utah.edu
At Tue, 10 Jul 2012 10:51:57 -0400, Eli Barzilay wrote:
20 minutes ago, Marijn wrote:
It seems to me that both these results cannot be correct
simultaneously, but I'll await the experts' opinion on that.
This does look weird:
#lang racket
(define-for-syntax (f stx) #`(let ([x
On 07/10/2012 10:51 AM, Eli Barzilay wrote:
20 minutes ago, Marijn wrote:
It seems to me that both these results cannot be correct
simultaneously, but I'll await the experts' opinion on that.
This does look weird:
#lang racket
(define-for-syntax (f stx) #`(let ([x 1]) #,stx))
An hour and a half ago, Matthew Flatt wrote:
It's natural --- but not correct --- to think that #` is responsible
for hygiene, in which case `(f #'x)' should keep the given `x'
separate from the `let'-bound `x' in the result.
Instead, hygiene is the responsibility of macro invocation, and
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Hi Stefan,
On 03-07-12 23:52, Stefan Israelsson Tampe wrote:
You do not need gensyms if you try to mimic or implement my
suggested #. . On the other hand when if you do this
(define (f stx) #`(let ((x 1)) #,stx))
and use this with
#`(let
Funny, for guile I get,
scheme@(guile-user) (define (f x) #`(let ((x 1)) #,x))
scheme@(guile-user) (define-syntax m (lambda (x) (syntax-case x () ((_)
#`(let ((x 2)) #,(f #'x))
scheme@(guile-user) (m)
$1 = 1
I ported the racket matcher to guile and worked in that environment, so
this
Hey!
Stefan Israelsson Tampe stefan.ita...@gmail.com skribis:
Stefan Israelsson Tampe stefan.ita...@gmail.com skribis:
Maybe this help to see what I'm after,
#'(let ((x v)) #.(f #'x))
=
(let-syntax ((g (lambda (stx) (syntax-case stx ((_ x) (f #'x)
#'(let ((x v)) (g x))
You do not need gensyms if you try to mimic or implement my suggested #. .
On the
other hand when if you do this
(define (f stx) #`(let ((x 1)) #,stx))
and use this with
#`(let ((x 2)) #,(f #'x))
the resulting expanded code would produce 1 which is not what you want.
So in the racket matcher I
Hi Stefan,
Stefan Israelsson Tampe stefan.ita...@gmail.com skribis:
Hygiene is harder to maintain. e.g. I kept on hitting this kind of code
snippets
#'(let ((x v))
#,(f rest #'x))
The problem with this code is hygiene, I need to make a gensym and use
with-syntax to bound x to that
Maybe this help to see what I'm after,
#'(let ((x v)) #.(f #'x))
=
(let-syntax ((g (lambda (stx) (syntax-case stx ((_ x) (f #'x)
#'(let ((x v)) (g x))
Now I would like to have a corresponding #.@ notation as well but can't
find an analog
for that :-(
/Stefan
On Mon, Jul 2, 2012 at
Hey!
Stefan Israelsson Tampe stefan.ita...@gmail.com skribis:
Maybe this help to see what I'm after,
#'(let ((x v)) #.(f #'x))
=
(let-syntax ((g (lambda (stx) (syntax-case stx ((_ x) (f #'x)
#'(let ((x v)) (g x))
Sorry, I fail to understand the problem you’re trying to solve.
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