* a list or map, followed or preceded by separators). For string
* and string_len, the char * must be UTF-8 encoded. string_len
* allows non-terminated strings and strings with embedded NULs
- * (though the handling of the latter is format-dependent).
+ * (though the handling of the latter is format-dependent). For
+ * string (but not string_len) the string pointer passed may be
+ * NULL.
*/
void (*string) (struct sprinter *, const char *);
void (*string_len) (struct sprinter *, const char *, size_t);