Hello everybody, hello Alex,
I noticed that when using `columnar` that changes to the format state
get swallowed. Digging into this, it's due to the copying of the state
before creating partial output from the following lines (fmt-column.scm,
l. 82f):
;; gen threads through it's own state, ignore result
(gen (fmt-set-writer! (copy-fmt-state st) output*))
All of the changes to `st` within the gen function will then ignored.
Now I am not exactly sure which changes we want to preserve, but I
believe that at least the `properties` should be kept, as they might
contain meaningful information (which is how I discovered this bug).
Would it make sense to preserve more information from the copied state
or should we leave it at that? Currently my fix (also attached) looks like:
;; gen threads through it's own state, copy over properties
(let ([st (gen (fmt-set-writer! (copy-fmt-state st) output*))])
(fmt-set-properties! orig-st (fmt-properties st)))
Let me know what you think, would be happy to see this included.
Cheers
Nik
diff --git a/fmt/0.8.14/fmt-column.scm b/fmt/0.8.14/fmt-column.scm
index 152bc3c..dd1f18b 100644
--- a/fmt/0.8.14/fmt-column.scm
+++ b/fmt/0.8.14/fmt-column.scm
@@ -79,8 +79,9 @@
(set! acc (cons (substring/shared str i) acc))))))
;; update - don't output or the string port will fill up
(fmt-update str st))
- ;; gen threads through it's own state, ignore result
- (gen (fmt-set-writer! (copy-fmt-state st) output*))
+ ;; gen threads through it's own state, copy over properties
+ (let ([st (gen (fmt-set-writer! (copy-fmt-state st) output*))])
+ (fmt-set-properties! orig-st (fmt-properties st)))
;; reduce # of remaining finite columns
(set! remaining (- remaining 1))
;; write any remaining accumulated output
