[m-rev.] diff: tweak comment

[Mark Brown]

Hi,

commit 81ce3a34592067704d6bcb78371a1ae4b018bc8b
Author: Mark Brown <mark at mercurylang.org>
Date:   Sat Mar 25 01:06:56 2023 +1100

    Tweak a comment.

    library/list.m:
            Make the same change as was suggested elsewhere, where the
            comment was being quoted.

diff --git a/library/list.m b/library/list.m
index 6c607231b..1c36bf84b 100644
--- a/library/list.m
+++ b/library/list.m
@@ -108,9 +108,9 @@
 :- mode append(in, out, in) is semidet.
 :- mode append(out, out, in) is multi.
 % The following mode is semidet in the sense that it does not
-% succeed more than once - but it does create a choice-point, which means
-% both that it is inefficient, and that the compiler can't deduce that
-% it is semidet. Use remove_suffix instead.
+% succeed more than once - but operationally, it does create a choice-point,
+% which means both that it is inefficient, and that the compiler can't deduce
+% that it is semidet. Use remove_suffix instead.
 % :- mode append(out, in, in) is semidet.

 :- func append(list(T), list(T)) = list(T).