Support keeping entirely capitalized words (optionally)

[ideasman42]

Often fully capitalized words are initials, and should not be changed, e.g.

• ISO Standard references - APA Style
• GNU General Public License
• Optimizing RAM Usage

... in these cases, instead of maintaining a list of acronyms, I think a reasonable rule of thumb is not to adjust fully capitalized words. Or at least have a rule to do so.

Note that this is how my much shorter script worked: https://emacs.stackexchange.com/a/66362/2418

[duckwork]

Dammit, this means my implementation still has bugs. I was just about to come over here to open an issue about capital letters at the end of a region not staying capitalized ...

However, the current main should properly keep these ALL-CAPS words capitalized; can you make sure it does?

EDIT on reading this comment over again I want to make it clear that the "dammit" at the beginning of it is directed at myself --- this issue has plagued me for some hours now!

DOUBLE EDIT I do want to note that on my Emacs at least, when capitalizing the phrases you've provided the acronyms stay capitalized. I'm running the latest main of titlecase.

[ideasman42]

Ah, then this is a bug, some titles I tried failed so I assumed it was unsupported, but as you state, this works sometimes too.

These fails for me:

• Emacs: API 29 -> Emacs: Api 29
• API API API -> Api Api Api
• API Three API -> API Three Api

[duckwork]

Hm, this is something. I thought at first it was just the last word logic being weird, but it might be something else.

However, the second one

• API API API -> Api Api Api

is correct, at least for this version of titlecase.el. If it detects the whole text is all-caps before title-casing, it lowercases everything first. Of course, I made this configurable too (see titlecase-normalize-functions).