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the debug macro
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Madhu
Apr 15, 2023, 11:24:05 AM4/15/23
to
I recently had to reinvent this, but I'm sure I've seen a version of it
on cll decades ago. Anyone remember which poster or post? I'm
interested to see how it was described.
```
(defmacro debug (&rest syms)
(let ((leader (if (stringp (car syms)) (pop syms) "DEBUG")))
(let ((format-string (format nil "~A: ~{~A=~~S~^, ~}~~&" leader syms)))
`(format t ,format-string ,@syms))))
```
The best docstring I could come up with is:
"\(DEBUG [\"DEBUG-MSG\"] [ITEMS...] \) prints DEBUG-MSG: [ITEM=VAL ...]
on standard output"
A slight advantage may be gleaned if the string and arguments to DEBUG
are treated as such:
```
(defmacro debug (&rest syms-and-strings)
(let* ((args nil)
(fmt-string
(with-output-to-string (stream)
(loop for (c . rest) on syms-and-strings do
(typecase c
(string (princ c stream))
((or (and symbol (not keyword)) (not atom))
(push c args)
(princ c stream)
(princ "=~S" stream))
(otherwise (prin1 c stream)))
(princ (if (endp rest) #\Newline #\Space) stream)))))
`(format t ,fmt-string ,@(nreverse args))))
```
But then it loses some of the declarative conciseness
on cll decades ago. Anyone remember which poster or post? I'm
interested to see how it was described.
```
(defmacro debug (&rest syms)
(let ((leader (if (stringp (car syms)) (pop syms) "DEBUG")))
(let ((format-string (format nil "~A: ~{~A=~~S~^, ~}~~&" leader syms)))
`(format t ,format-string ,@syms))))
```
The best docstring I could come up with is:
"\(DEBUG [\"DEBUG-MSG\"] [ITEMS...] \) prints DEBUG-MSG: [ITEM=VAL ...]
on standard output"
A slight advantage may be gleaned if the string and arguments to DEBUG
are treated as such:
```
(defmacro debug (&rest syms-and-strings)
(let* ((args nil)
(fmt-string
(with-output-to-string (stream)
(loop for (c . rest) on syms-and-strings do
(typecase c
(string (princ c stream))
((or (and symbol (not keyword)) (not atom))
(push c args)
(princ c stream)
(princ "=~S" stream))
(otherwise (prin1 c stream)))
(princ (if (endp rest) #\Newline #\Space) stream)))))
`(format t ,fmt-string ,@(nreverse args))))
```
But then it loses some of the declarative conciseness
Madhu
May 25, 2023, 6:18:40 AM5/25/23
to
* In <m335512...@leonis4.robolove.meer.net> :
I Wrote on Sat, 15 Apr 2023 20:54:19 +0530:
> I recently had to reinvent this, but I'm sure I've seen a version of it
> on cll decades ago. Anyone remember which poster or post? I'm
> interested to see how it was described.
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