I was wondering if anyone could suggest a method of debugging "define-macro" expressions so that I can see what is actually being generated by the macro system (e.g. by preventing evaluation of the resulting macro, and printing it)? Otherwise I get a cryptic messages like "unbound unquote", and "ill-formed expression", but without any hints what is causing the grief in the generated code.
Thanks, Christopher Diggins
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Your friends here are lambda and pp. Gambit will always expand macros inside a lambda so if you have file x.scm containing :
------------
(define-macro (when test body) `(if ,test (begin ,@body)))
(define (foo x) (when (= x 0) (write 'yo))) ------------
you can do the following
Gambit v4.0.0
(load "x")
"C:\Jazz\dev\jazz\x.scm"
(pp foo)
(lambda (x) (if (= x 0) (begin write 'yo)))
alternatively, if your code is compiled, I suggest always compiling it with -debug that adds no runtime penalty and keeps the source code so you can do
C:\Jazz\dev\jazz>gsc -debug x
C:\Jazz\dev\jazz>gsc Gambit v4.0.0
(load "x")
"C:\Jazz\dev\jazz\x.o1"
(pp foo)
(##lambda (x) (when (= x 0) (write 'yo)))
Guillaume On 10/26/07, Christopher Diggins cdiggins@gmail.com wrote:
I was wondering if anyone could suggest a method of debugging "define-macro" expressions so that I can see what is actually being generated by the macro system (e.g. by preventing evaluation of the resulting macro, and printing it)? Otherwise I get a cryptic messages like "unbound unquote", and "ill-formed expression", but without any hints what is causing the grief in the generated code.
Thanks, Christopher Diggins _______________________________________________ Gambit-list mailing list Gambit-list@iro.umontreal.ca https://webmail.iro.umontreal.ca/mailman/listinfo/gambit-list
While reading my post I noticed that (pp foo) will not have the macros expanded in the compiled version. Of course, the Gambit compiler preserves the copy of the source code *before* doing macro expansions so it is exactly as in the source file. Sorry about that. Guess what that means is that the interpreter is your other friend ;)
On 10/26/07, Guillaume Cartier gcartier@jazzscheme.org wrote:
Your friends here are lambda and pp. Gambit will always expand macros inside a lambda so if you have file x.scm containing :
(define-macro (when test body) `(if ,test (begin ,@body)))
(define (foo x) (when (= x 0) (write 'yo)))
you can do the following
Gambit v4.0.0
(load "x")
"C:\Jazz\dev\jazz\x.scm"
(pp foo)
(lambda (x) (if (= x 0) (begin write 'yo)))
alternatively, if your code is compiled, I suggest always compiling it with -debug that adds no runtime penalty and keeps the source code so you can do
C:\Jazz\dev\jazz>gsc -debug x
C:\Jazz\dev\jazz>gsc Gambit v4.0.0
(load "x")
"C:\Jazz\dev\jazz\x.o1"
(pp foo)
(##lambda (x) (when (= x 0) (write 'yo)))
Guillaume On 10/26/07, Christopher Diggins cdiggins@gmail.com wrote:
I was wondering if anyone could suggest a method of debugging "define-macro" expressions so that I can see what is actually being generated by the macro system (e.g. by preventing evaluation of the resulting macro, and printing it)? Otherwise I get a cryptic messages like "unbound unquote", and "ill-formed expression", but without any hints what is causing the grief in the generated code.
Thanks, Christopher Diggins _______________________________________________ Gambit-list mailing list Gambit-list@iro.umontreal.ca https://webmail.iro.umontreal.ca/mailman/listinfo/gambit-list
Thank you very much for your prompt help Guillaume and David.
- Christopher
On 10/26/07, Guillaume Cartier gcartier@jazzscheme.org wrote:
While reading my post I noticed that (pp foo) will not have the macros expanded in the compiled version. Of course, the Gambit compiler preserves the copy of the source code *before* doing macro expansions so it is exactly as in the source file. Sorry about that. Guess what that means is that the interpreter is your other friend ;)
On 10/26/07, Guillaume Cartier gcartier@jazzscheme.org wrote:
Your friends here are lambda and pp. Gambit will always expand macros
inside a lambda so if you have file x.scm containing :
(define-macro (when test body) `(if ,test (begin ,@body)))
(define (foo x) (when (= x 0) (write 'yo)))
you can do the following
Gambit v4.0.0
(load "x")
"C:\Jazz\dev\jazz\x.scm"
(pp foo)
(lambda (x) (if (= x 0) (begin write 'yo)))
alternatively, if your code is compiled, I suggest always compiling it
with -debug that adds no runtime penalty and keeps the source code so you can do
C:\Jazz\dev\jazz>gsc -debug x
C:\Jazz\dev\jazz>gsc Gambit v4.0.0
(load "x")
"C:\Jazz\dev\jazz\x.o1"
(pp foo)
(##lambda (x) (when (= x 0) (write 'yo)))
Guillaume
On 10/26/07, Christopher Diggins <cdiggins@gmail.com > wrote:
I was wondering if anyone could suggest a method of debugging "define-macro" expressions so that I can see what is actually being generated by the macro system (e.g. by preventing evaluation of the resulting macro, and printing it)? Otherwise I get a cryptic messages like "unbound unquote", and "ill-formed expression", but without any hints what is causing the grief in the generated code.
Thanks, Christopher Diggins _______________________________________________ Gambit-list mailing list Gambit-list@iro.umontreal.ca
https://webmail.iro.umontreal.ca/mailman/listinfo/gambit-list
Gambit-list mailing list Gambit-list@iro.umontreal.ca https://webmail.iro.umontreal.ca/mailman/listinfo/gambit-list
Hi,
You can use this code to trace the expansion of your macros:
(##define-macro (define-macro args . body) (let ((all (gensym))) `(##define-macro (,(car args) . ,all) (let ((exp (apply (lambda ,(cdr args) . ,body) ,all))) (pp (list (cons ',(car args) ,all) '-> exp)) exp))))
For example:
(define-macro (when c . e) `(if ,c (begin . ,e))) (when #t (when #f (pp 'foo)) 2)
((when #t (when #f (pp 'foo)) 2) -> (if #t (begin (when #f (pp 'foo)) 2))) ((when #f (pp 'foo)) -> (if #f (begin (pp 'foo)))) 2
Etienne Laurin
On Fri, Oct 26, 2007 at 08:49:15AM -0400, Christopher Diggins wrote:
I was wondering if anyone could suggest a method of debugging "define-macro" expressions so that I can see what is actually being generated by the macro system (e.g. by preventing evaluation of the resulting macro, and printing it)? Otherwise I get a cryptic messages like "unbound unquote", and "ill-formed expression", but without any hints what is causing the grief in the generated code.
Thanks, Christopher Diggins _______________________________________________ Gambit-list mailing list Gambit-list@iro.umontreal.ca https://webmail.iro.umontreal.ca/mailman/listinfo/gambit-list
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Christopher Diggins -
Etienne Laurin -
Guillaume Cartier