On Tue, Dec 22, 2020, Dave Kemper wrote: > It seemed a minor thing before, but now that it's tripped up the > author of possibly the most elaborate macro package published in > the roff language's 50-year history, I wonder if that's worth > revisiting.
Being said author, I can confirm that yes, I did indeed get tripped up in exactly the way Dave described: quick check of paragraph one to refresh my memory, not reading under the fold, forgetting that sentence space means additional space. I obviously knew once or mom wouldn't have macros for manipulating word and sentence spacing, but it's something I haven't had to think about in years. That said, while the info entry for .ss is accurate as is, the material does need to be re-ordered somewhat. First off, a reader of the entry, looking for information on sentence spacing, and rationally assuming 'ss' stands for 'sentence space,' is presented, surprisingly, with "Change the size of a space between *words.*" Then, because of the capitalization of the argument descriptions, the eye tends to jump to: "Initially both the WORD_SPACE_SIZE and SENTENCE_SPACE_SIZE are 12," which, without some explanation of sentence space, leads to the conclusion that the value of sentence_space_size is discrete. The erroneous conclusion then appears to be confirmed in the second paragraph: "If the second argument is not given, sentence space size is set to WORD_SPACE_SIZE," which, as before, suggests "is equal to," not "is added to", word space size. So, yes, it's worth re-working the info .ss entry. Perhaps begin with something like: "Change the size of the space between words and sentences. The space between sentences is derived by adding WORD_SPACE_SIZE and SENTENCE_SPACE_SIZE. Thus '.ss 12 0' results in no additional space being added between sentences, whereas '.ss 12 12' results in an additional 12 units of space between sentences." -- Peter Schaffter https://www.schaffter.ca