The problem was that in the final recursive call, when imap_go would return Nil, the index argument was out-of-bounds. And because imap_go was strict in all arguments, imap_go would make the Nil undefined.
Subsequently applying reverse where the Nil is undefined, gives us a complete vector that is undefined, given that reverse is strict in its vector argument.
Still TODO:
[x] Write a changelog entry (see changelog/README.md)
[x] Check copyright notices are up to date in edited files
Fixes #2542
The problem was that in the final recursive call, when
imap_gowould returnNil, the index argument was out-of-bounds. And becauseimap_gowas strict in all arguments,imap_gowould make theNilundefined.Subsequently applying
reversewhere theNilis undefined, gives us a complete vector that is undefined, given thatreverseis strict in its vector argument.Still TODO: