How do I get Emacs to fill sentences, but not paragraphs?

Question

I\'ve seen at least two recommendations on StackOverflow to insert newlines between sentences when editing LaTeX documents. The reason being that the practice facilitates so

Answer 1

If you put a comment marker at the end of each sentence, Emacs knows not to move the next line inside the comment:

chat chat chat.%
A new sentence
with goofed up wrapping that needs to be fixed.%
Mumble mumble%

Then M-q fills each sentence separately, at least in AUCTeX 11.85. (If you test this in Emacs, there seems to be a bug where if this is the first paragraph in the buffer and you type M-q, you get an error message. Just put a newline before the text to work around it.)

If you don't want to type the comment characters, you could take LaTeX-fill-paragraph and modify it so that sentence-ending punctuation at end of line works similarly to comments.