The relevant part of the CLL for lerfu-forming cmavo is chapter 17, specifically, sections 3, 5, 6, 7 and 14. I find no internal contradictions in the text, and its completeness is satisfactory, except for a small concern about alphabet and font shifts, which I will return to shortly.
The words in this paradigm has seen almost no use outside the language definition materials. This probably is because they are related to spelling, which is a predominantly oral activity. (Finding occurrences of "aitch" in an English corpus this small would probably give similar results.) It is perhaps worth mentioning that I discovered the members of LAU, TEI and FOI on a Wiki page titled "Cmavo that are a ghastly waste of precious monosyllabic cmavo space"...
However, I'm happy to report that "boi" is being used, and always correctly. Some examples:
The Book does not say explicitly how far the alphabet shift (zai and friends) and the font shift lasts. Presumably, it must last for more than one letter, because of the existence of the font-and-alphabet shift cancelling cmavo "na'a" (p 418), and the illustration on p 412 ("zai xanlerfu bu ly .obu jy by .abu ny.").
Since there is a possibillity of specifying categories such as font face and text size separately (according to examples 5.5 - 5.7), I have assumed that the intention is for the ce'a shift to take effect until another ce'a shift is applied to the same category. My cmavo definition of ce'a reflects that. I will leave it to the shepherd of BY to take care of the other cmavo that act similarly.
Terminates a letteral sequence or a numeral.
- end letteral
- end numeral
- mamta fa le se jorne be zy. boi bei lo se xabju be'o
- The mother who is a thing to which Z is joined at the dwelling. (bad translation... Thanks, Lojbot, for being weird.)
Combines with the previous word to make a Lojban letteral, provided that it is not one of the quote cmavo (ZO, ZOI, LOhU) or one of the erasure cmavo (SI, SA, SU), ZEI, or FAhO. If the aforementioned previous word is already a letteral, the resulting letteral will not necessarily be the same, for instance, "ky. bu" is different from "ky". In addition to single words, bu can be combined with a letteral that is already a composite of a word+bu, a zei-lujvo, a zo-quoted word, a lo'u-quoted string of words or a zoi-quoted foreign text. If there is no previous word, "bu" is in error; this entails that "bu bu" by itself is also ungrammatical.
- magic word
- co'o .o bu
- Goodbye, O!
- Converts the following lerfu to a font change letteral; font changes affect every letteral after them in the letteral sequence, and only those letterals. More than one can be in effect at a time, but if two directly contradict each other, only the latest one applies.
- mi platu lonu ciska ce'a xelvetikas bu lu ganse po'o li'u : I plan on writing *in helvetica* "Only Observe".
- Marks the end of a combination letteral; the resulting letteral is some unspecified (lexically defined) combination of all the enclosed letterals.
- .i me'o tei xyxycycy foi cu pa mei xu : XXCC is a set with only one member?
- Converts the following letteral to punctuation. The following letteral may be a single letteral word, a combination letteral with tei and foi, or a letteral combined with bu. It may also be prefixed by lau.
- la'a na go'i lau ba'e : Probably not!
(this is the only example on record that isn't just somebody saying "lau" or quoting it with zo)
- Converts the following letteral to the opposite case, e.g. convert an uppercase letteral to lowercase, or a lowercase letteral to uppercase. The following letteral may be a single letteral word, a combination letteral with tei and foi, or a letteral combined with bu. It may also be prefixed by lau.
- tau xy ny : XN
- li ma'o tau i bu boi te'u vei xy pi'i tau ny jbidu'o li de'o re vei ny te'a ci .i ri du li xy pi'i re bi'e de'o ny: *bunch of math stuff*
- Marks the beginning of a combination letteral; the resulting letteral is some unspecified (lexically defined) combination of all the enclosed letterals.
- .u'isai zo'e pe tei xykycydy foi mutce zdile : Hah, those xkcd things are hilarious.
- Marks the following letteral as an alphabet shift. The following letteral may be a single letteral word, a combination letteral with tei and foi, or a letteral combined with bu. It may also be prefixed by lau. Alphabet shifts affect every letteral after them in the letteral sequence, and only those letterals.
- There is no usage of this that isn't a typo of za'i or a zo quote.
- end letteral. end numeral
- sign. character. symbol.
- change font to. in font.
- characters joined together
- punctuation symbol. punctuation sign.
- character composed of
- change alphabet to. in alphabet.
Given that Lojban does not seem to be intended for holding multilingual spelling bees, and that a dictionary containing many unused cmavo with bizarre functions could confuse learners of the language, the BPFK does not recommend to include the alphabet shift zai in learning materials intended even for advanced learners. The cmavo should not be reassigned to have other meanings, however.
This proposal entails the following changes:
- Codify that letteral shifts last until the end of the letteral string or until superseded by another shift in the same category.
- Replace old definitions with new ones (see above)
- Add new keywords (see above)
It is my opinion that these changes are mere clarifications, and will not impact or invalidate usage, current or past. It also agrees with the letter shifts in BPFK Section: Lerfu Shifts.