Given the following input file: ~~~markdown byte ASCII meaning ---- ------- ---------- 0 NUL indicates end of filename 56 period used for . and .. directory entries 57 slash used to separate components in a pathname --- title: "Obnam2—a backup system" author: Lars Wirzenius template: python ... ~~~ When I run sp-docgen, it fails: ~~~sh 09:41 exolobe1:~/.../git [debug]$ cargo run -q --bin sp-docgen obnam.md -o obnam.html Error: invalid length 0, expected a tuple of size 3 at line 1 column 31 [PREVIOUS COMMAND EXIT: 1] 09:42 exolobe1:~/.../git [debug]$ ~~~