[chrismorgan]

To do this properly, you have to map versifications, because some systems use different conventions. As the most significant and pervasive example, some systems treat the title of psalms as verse one (French generally does this), while others treat it as separate (verse zero, effectively; English generally does this), so if you just reuse numbers across such transitions you’ll get consistent off-by-one errors. There are quite a few other similar off-by-one errors, and occasionally more, throughout.

https://wiki.crosswire.org/Alternate_Versification is a decent starting point for looking into the topic, with SWORD’s canon_.h files fairly tolerable for showing the number of verses in each chapter. Unfortunately, SWORD has never gone as far as doing proper mapping* between versifications for some reason—they have some basic mapping somewhere or other, but I can’t remember offhand where or what it is, as I only briefly looked into it five years or so ago.

The most significant differences occur when you switch languages (there are quite a few differences if you switch from English to French or to many Indic languages), but there may be some differences between translations within a language too, e.g. SWORD’s NRSV versification has an extra verse in 3 John and Revelation 12 compared to its KJV versification.