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Re: [Chicken-users] ANN: eping
From: |
Michele La Monaca |
Subject: |
Re: [Chicken-users] ANN: eping |
Date: |
Thu, 22 Aug 2013 17:53:46 +0200 |
On Thu, Aug 22, 2013 at 4:54 PM, John Cowan <address@hidden> wrote:
> Your macro will work as far as handling bound and unbound symbols; of
> course, symbols *lexically* bound will not be seen, only global symbols.
> That's the nature of Scheme's eval.
I think eval usage (and limitations) can be avoided: For example:
(define-syntax eping
(syntax-rules ()
((_ h)
(handle-exceptions exn
(_eping (symbol->string '|h|))
(let ((t h)) (_eping t))))))
as regarding (symbol->string '|h|), what you are saying is that in
this context it is equivalent to (symbol->string 'h) and that one
happens to work only because Chicken considers '192.168.0.1 a valid
symbol while in standard Scheme is not. Right? Anyway, it seems to me
quite a limitation that IP addresses are not valid Scheme symbols and
something that should be fixed if it is an artificially imposed
limitation.
> You should go and read "JRM's Syntax-rules Primer for the Merely
> Eccentric" <http://www.phyast.pitt.edu/~micheles/syntax-rules.pdf> to
> get a feel for what syntax-rules macros can and cannot do. Just stop
> reading when you no longer follow the text: that means you've absorbed
> as much as you can for now. When you need more, go back to it.
Thanks for the pointer.
Michele
- Re: [Chicken-users] ANN: eping, Michele La Monaca, 2013/08/22
- Re: [Chicken-users] ANN: eping, Michele La Monaca, 2013/08/22
- Re: [Chicken-users] ANN: eping, Michele La Monaca, 2013/08/22
- Re: [Chicken-users] ANN: eping, John Cowan, 2013/08/22
- Re: [Chicken-users] ANN: eping, John Maxwell, 2013/08/22
- Re: [Chicken-users] ANN: eping,
Michele La Monaca <=
- Re: [Chicken-users] ANN: eping, John Cowan, 2013/08/22
- Re: [Chicken-users] ANN: eping, Michele La Monaca, 2013/08/22
- Re: [Chicken-users] ANN: eping, Michele La Monaca, 2013/08/23
- Re: [Chicken-users] ANN: eping, Jörg F . Wittenberger, 2013/08/24
- Re: [Chicken-users] ANN: eping, John Cowan, 2013/08/24
- Re: [Chicken-users] ANN: eping, Michele La Monaca, 2013/08/26