btw I forgot to say that the macro stepper of drscheme is great to see this at
work. If you try on your example, you'll see that the 'return' identifier in
(lambda (return) ...) is not the same color as the 'return' identifier in your
test.
-- Éric
On Jul 8, 2010, at 6:59 PM, Eric Tanter wrot
Eric Tanter wrote at 07/08/2010 06:59 PM:
You need to circumvent hygiene to do what you're after; for this, you need to
use syntax-case.
Scheme, from which Racket has grown, very much wants macros to be
hygienic. If you (Manu) are new to macros in Scheme, I'd encourage you
to first find
That's an hygiene issue: syntax-rules is hygienic, meaning (in that case) that
a binding instance introduced by the macro does not capture instances in the
original code.
You need to circumvent hygiene to do what you're after; for this, you need to
use syntax-case.
You can look at chapter 36
Hello
I am having a problem with the following macro:
(define-syntax lambda-r
(syntax-rules ()
((_ args exp ...)
(lambda args
(call-with-current-continuation
(lambda (return)
exp ... ))
it's meant to define a lambda-r form, which wraps a lambda in call/
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