The following two listings constitute the formal grammar of Lojban. The first version is written in the YACC language, which is used to describe parsers, and has been used to create a parser for Lojban texts. This parser is available from the Logical Language Group. The second listing is in Extended Backus-Naur Form (EBNF) and represents the same grammar in a more human-readable form. (In case of discrepancies, the YACC version is official.) There is a cross-reference listing for each format that shows, for each selma'o and rule, which rules refer to it.
The Lojban machine parsing algorithm is a multi-step process. The YACC machine grammar presented here is an amalgam of those steps, concatenated so as to allow YACC to verify the syntactic ambiguity of the grammar. YACC is used to generate a parser for a portion of the grammar, which is LALR1 (the type of grammar that YACC is designed to identify and process successfully), but most of the rest of the grammar must be parsed using some language-coded processing.
Step 1 – Lexing
From phonemes, stress, and pause, it is possible to resolve Lojban unambiguously into a stream of words. Any machine processing of speech will have to have some way to deal with “non-Lojban” failures of fluent speech, of course. The resolved words can be expressed as a text file using Lojban's phonetic spelling rules.
The following steps assume that there is the possibility of non-Lojban text within the Lojban text (delimited appropriately). Such non-Lojban text may not be reducible from speech phonetically. However, step 2 allows the filtering of a phonetically transcribed text stream, to recognize such portions of non-Lojban text where properly delimited, without interference with the parsing algorithm.
Step 2 – Filtering
From start to end, performing the following filtering and lexing tasks using the given order of precedence in case of conflict:
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If the Lojban word zoi (selma'o ZOI) is identified, take the following Lojban word (which should be end delimited with a pause for separation from the following non-Lojban text) as an opening delimiter. Treat all text following that delimiter, until that delimiter recurs after a pause, as grammatically a single token (labelled “YACC rule #699” in this grammar). There is no need for processing within this text except as necessary to find the closing delimiter.
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If the Lojban word zo (selma'o ZO) is identified, treat the following Lojban word as a token labelled “YACC rule #698”, instead of lexing it by its normal grammatical function.
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If the Lojban word lo'u (selma'o LOhU) is identified, search for the closing delimiter le'u (selma'o LEhU), ignoring any such closing delimiters absorbed by the previous two steps. The text between the delimiters should be treated as the single token “YACC rule #697”.
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Categorize all remaining words into their Lojban selma'o category, including the various delimiters mentioned in the previous steps. In all steps after step 2, only the selma'o token type is significant for each word.
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If the word si (selma'o SI) is identified, erase it and the previous word (or token, if the previous text has been condensed into a single token by one of the above rules).
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If the word sa (selma'o SA) is identified, erase it and all preceding text as far back as necessary to make what follows attach to what precedes. (This rule is hard to formalize and may receive further definition later.)
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If the word su (selma'o SU) is identified, erase it and all preceding text back to and including the first preceding token word which is in one of the selma'o: NIhO, LU, TUhE, and TO. However, if speaker identification is available, a SU shall only erase to the beginning of a speaker's discourse, unless it occurs at the beginning of a speaker's discourse. (Thus, if the speaker has said something, two adjacent uses of su are required to erase the entire conversation.
Step 3 – Termination
If the text contains a FAhO, treat that as the end-of-text and ignore everything that follows it.
Step 4 – Absorption of Grammar-Free Tokens
In a new pass, perform the following absorptions (absorption means that the token is removed from the grammar for processing in following steps, and optionally reinserted, grouped with the absorbing token after parsing is completed).
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Token sequences of the form any - (ZEI - any) ..., where there may be any number of ZEIs, are merged into a single token of selma'o BRIVLA.
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Absorb all selma'o BAhE tokens into the following token. If they occur at the end of text, leave them alone (they are errors).
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Absorb all selma'o BU tokens into the previous token. Relabel the previous token as selma'o BY.
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If selma'o NAI occurs immediately following any of tokens UI or CAI, absorb the NAI into the previous token.
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Absorb all members of selma'o DAhO, FUhO, FUhE, UI, Y, and CAI into the previous token. All of these null grammar tokens are permitted following any word of the grammar, without interfering with that word's grammatical function, or causing any effect on the grammatical interpretation of any other token in the text. Indicators at the beginning of text are explicitly handled by the grammar.
Step 5 – Insertion of Lexer Lexemes
Lojban is not in itself LALR1. There are words whose grammatical function is determined by following tokens. As a result, parsing of the YACC grammar must take place in two steps. In the first step, certain strings of tokens with defined grammars are identified, and either
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are replaced by a single specified “lexer token” for step 6, or
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the lexer token is inserted in front of the token string to identify it uniquely.
The YACC grammar included herein is written to make YACC generation of a step 6 parser easy regardless of whether a. or b. is used. The strings of tokens to be labelled with lexer tokens are found in rule terminals labelled with numbers between 900 and 1099. These rules are defined with the lexer tokens inserted, with the result that it can be verified that the language is LALR1 under option b. after steps 1 through 4 have been performed. Alternatively, if option a. is to be used, these rules are commented out, and the rule terminals labelled from 800 to 900 refer to the lexer tokens without the strings of defining tokens. Two sets of lexer tokens are defined in the token set so as to be compatible with either option.
In this step, the strings must be labelled with the appropriate lexer tokens. Order of inserting lexer tokens IS significant, since some shorter strings that would be marked with a lexer token may be found inside longer strings. If the tokens are inserted before or in place of the shorter strings, the longer strings cannot be identified.
If option a. is chosen, the following order of insertion works correctly (it is not the only possible order): A, C, D, B, U, E, H, I, J, K, M, N, G, O, V, W, F, P, R, T, S, Y, L, Q. This ensures that the longest rules will be processed first; a PA+MAI will not be seen as a PA with a dangling MAI at the end, for example.
Step 6 – YACC Parsing
YACC should now be able to parse the Lojban text in accordance with the rule terminals labelled from 1 to 899 under option 5a, or 1 to 1099 under option 5b. Comment out the rules beyond 900 if option 5a is used, and comment out the 700-series of lexer-tokens, while restoring the series of lexer tokens numbered from 900 up.
%token A_501 eks; basic afterthought logical connectives %token BAI_502 modal operators %token BAhE_503 next word intensifier %token BE_504 sumti link to attach sumti to a selbri %token BEI_505 multiple sumti separator between BE, BEI %token BEhO_506 terminates BE/BEI specified descriptors %token BIhI_507 interval component of JOI %token BO_508 joins two units with shortest scope %token BRIVLA_509 any brivla %token BU_511 turns any word into a BY lerfu word %token BY_513 individual lerfu words %token CAhA_514 specifies actuality/potentiality of tense %token CAI_515 afterthought intensity marker %token CEI_516 pro-bridi assignment operator %token CEhE_517 afterthought term list connective %token CMENE_518 Lojbanized names; require consonant end, as well as a pause before and after them %token CO_519 tanru inversion %token COI_520 vocative marker permitted inside cmevla; must always be followed by pause or DOI %token CU_521 separator between head sumti and selbri %token CUhE_522 tense/modal question %token DAhO_524 cancel anaphora/cataphora assignments %token DOI_525 vocative marker %token DOhU_526 terminator for DOI-marked vocatives %token FA_527 modifier head generic case tag %token FAhA_528 superdirections in space %token FAhO_529 normally elided “done pause” to indicate end of utterance string %token FEhE_530 space interval mod flag %token FEhU_531 ends bridi to modal conversion %token FIhO_532 marks bridi to modal conversion %token FOI_533 end compound lerfu %token FUhE_535 open long scope for indicator %token FUhO_536 close long scope for indicator %token GA_537 geks; forethought logical connectives %token GEhU_538 marker ending GOI relative clauses %token GI_539 forethought medial marker %token GIhA_541 logical connectives for bridi-tails %token GOI_542 attaches a sumti modifier to a sumti %token GOhA_543 pro-bridi %token GUhA_544 GEK for tanru units, corresponds to JEKs %token I_545 sentence link %token JA_546 jeks; logical connectives within tanru %token JAI_547 modal conversion flag %token JOI_548 non-logical connectives %token KEhE_550 right terminator for KE groups %token KE_551 left long scope marker %token KEI_552 right terminator, NU abstractions %token KI_554 multiple utterance scope for tenses %token KOhA_555 sumti anaphora %token KU_556 right terminator for descriptions, etc. %token KUhO_557 right terminator, NOI relative clauses %token LA_558 name descriptors %token LAU_559 lerfu prefixes %token LAhE_561 sumti qualifiers %token LE_562 sumti descriptors %token LEhU_565 possibly ungrammatical text right quote %token LI_566 convert number to sumti %token LIhU_567 grammatical text right quote %token LOhO_568 elidable terminator for LI %token LOhU_569 possibly ungrammatical text left quote %token LU_571 grammatical text left quote %token LUhU_573 LAhE close delimiter %token ME_574 converts a sumti into a tanru_unit %token MEhU_575 terminator for ME %token MOhI_577 motion tense marker %token NA_578 bridi negation %token NAI_581 attached to words to negate them %token NAhE_583 scalar negation %token NIhO_584 new paragraph; change of subject %token NOI_585 attaches a subordinate clause to a sumti %token NU_586 abstraction %token NUhI_587 marks the start of a termset %token NUhU_588 marks the middle and end of a termset %token PEhE_591 afterthought termset connective prefix %token PU_592 directions in time %token RAhO_593 flag for modified interpretation of GOhI %token ROI_594 converts number to extensional tense %token SA_595 metalinguistic eraser to the beginning of the current utterance %token SE_596 conversions %token SEI_597 metalinguistic bridi insert marker %token SEhU_598 metalinguistic bridi end marker %token SI_601 metalinguistic single word eraser %token SOI_602 reciprocal sumti marker %token SU_603 metalinguistic eraser of the entire text %token TAhE_604 tense interval properties %token TEI_605 start compound lerfu %token TO_606 left discursive parenthesis %token TOI_607 right discursive parenthesis %token TUhE_610 multiple utterance scope mark %token TUhU_611 multiple utterance end scope mark %token UI_612 attitudinals, observationals, discursives %token VA_613 distance in space-time %token VAU_614 end simple bridi or bridi-tail %token VEhA_615 space-time interval size %token VIhA_616 space-time dimensionality marker %token VUhO_617 glue between logically connected sumti and relative clauses %token XI_618 subscripting operator %token Y_619 hesitation %token ZAhO_621 event properties – prospective, etc. %token ZEhA_622 time interval size tense %token ZEI_623 lujvo glue %token ZI_624 time distance tense %token ZIhE_625 conjoins relative clauses %token ZO_626 single word metalinguistic quote marker %token ZOI_627 delimited quote marker %token ZOhU_628 prenex terminator (not elidable) %token BIhE_650 prefix for high-priority MEX operator %token BOI_651 number or lerfu-string terminator %token FUhA_655 reverse Polish flag %token GAhO_656 open/closed interval markers for BIhI %token JOhI_657 flags an array operand %token KUhE_658 MEX forethought delimiter %token MAI_661 change numbers to utterance ordinals %token MAhO_662 change MEX expressions to MEX operators %token MOI_663 change number to selbri %token MOhE_664 change sumti to operand, inverse of LI %token NAhU_665 change a selbri into an operator %token NIhE_666 change selbri to operand; inverse of MOI %token NUhA_667 change operator to selbri; inverse of MOhE %token PA_672 numbers and numeric punctuation %token PEhO_673 forethought (Polish) flag %token TEhU_675 closing gap for MEX constructs %token VEI_677 left MEX bracket %token VEhO_678 right MEX bracket %token VUhU_679 MEX operator %token any_words_697 a string of lexable Lojban words %token any_word_698 any single lexable Lojban words %token anything_699 a possibly unlexable phoneme string The following tokens are the actual lexer tokens. The _900 series tokens are duplicates that allow limited testing of lexer rules in the context of the total grammar. They are used in the actual parser, where the 900 series rules are found in the lexer. %token lexer_ A_701 flags a MAI utterance ordinal %token lexer_ B_702 flags an EK unless EK_BO, EK_KE %token lexer_ C_703 flags an EK_BO %token lexer_ D_704 flags an EK_KE %token lexer_ E_705 flags a JEK %token lexer_ F_706 flags a JOIK %token lexer_ G_707 flags a GEK %token lexer_ H_708 flags a GUhEK %token lexer_ I_709 flags a NAhE_BO %token lexer_ J_710 flags a NA_KU %token lexer_ K_711 flags an I_BO (option. JOIK/JEK lexer tags) %token lexer_ L_712 flags a PA, unless MAI (then lexer A) %token lexer_ M_713 flags a GIhEK_BO %token lexer_ N_714 flags a GIhEK_KE %token lexer_ O_715 flags a modal operator BAI or compound %token lexer_ P_716 flags a GIK %token lexer_ Q_717 flags a lerfu_string unless MAI (then lexer_A) %token lexer_ R_718 flags a GIhEK, not BO or KE %token lexer_ S_719 flags simple I %token lexer_ T_720 flags I_JEK %token lexer_ U_721 flags a JEK_BO %token lexer_ V_722 flags a JOIK_BO %token lexer_ W_723 flags a JOIK_KE %token lexer_ X_724 null %token lexer_ Y_725 flags a PA_MOI %token lexer_A_905 : lexer_A_701 utt_ordinal_root_906 %token lexer_B_910 : lexer_B_702 EK_root_911 %token lexer_C_915 : lexer_C_703 EK_root_911 BO_508 %token lexer_D_916 : lexer_D_704 EK_root_911 KE_551 %token lexer_E_925 : lexer_E_705 JEK_root_926 %token lexer_F_930 : lexer_F_706 JOIK_root_931 %token lexer_G_935 : lexer_G_707 GA_537 %token lexer_H_940 : lexer_H_708 GUhA_544 %token lexer_I_945 : lexer_I_709 NAhE_583 BO_508 %token lexer_J_950 : lexer_J_710 NA_578 KU_556 %token lexer_K_955 : lexer_K_711 I_432 BO_508 %token lexer_L_960 : lexer_L_712 number_root_961 %token lexer_M_965 : lexer_M_713 GIhEK_root_991 BO_508 %token lexer_N_966 : lexer_N_714 GIhEK_root_991 KE_551 %token lexer_O_970 : lexer_O_715 simple_tense_modal_972 %token lexer_P_980 : lexer_P_716 GIK_root_981 %token lexer_Q_985 : lexer_Q_717 lerfu_string_root_986 %token lexer_R_990 : lexer_R_718 GIhEK_root_991 %token lexer_S_995 : lexer_S_719 I_545 %token lexer_T_1000 : lexer_T_720 I_545 simple_JOIK_JEK_957 %token lexer_U_1005 : lexer_U_721 JEK_root_926 BO_508 %token lexer_V_1010 : lexer_V_722 JOIK_root_931 BO_508 %token lexer_W_1015 : lexer_W_723 JOIK_root_931 KE_551 %token lexer_X_1020 null %token lexer_Y_1025 : lexer_Y_725 number_root_961 MOI_663 %start YACC rule #0 %% text_0 : YACC rule #1 | YACC rule #411 YACC rule #1 | YACC rule #32 YACC rule #1 | YACC rule #404 YACC rule #1 | YACC rule #411 YACC rule #32 YACC rule #1 | YACC rule #581 YACC rule #0 ; text_A_1 : YACC rule #422 YACC rule #2 incomplete JOIK_JEK without preceding I compare note on YACC rule #10 | YACC rule #2 ; text_B_2 : YACC rule #819 YACC rule #2 | YACC rule #820 YACC rule #2 | YACC rule #811 YACC rule #2 | YACC rule #410 YACC rule #3 | YACC rule #3 ; text_C_3 : YACC rule #4 Only indicators which follow certain selma'o: cmevla, YACC rule #607, YACC rule #571, and the lexer_K and lexer_S I_roots and compounds, and at the start of text(_0), will survive the lexer; all other valid ones will be absorbed. The only strings for which indicators generate a potential ambiguity are those which contain NAI. An indicator cannot be inserted in between a token and its negating NAI, else you can't tell whether it is the indicator or the original token being negated. | empty An empty text is legal; formerly this was handled by the explicit appearance of YACC rule #529, but this is now absorbed by the preparser. ; paragraphs_4 : YACC rule #10 | YACC rule #10 YACC rule #410 YACC rule #4 ; paragraph_10 : YACC rule #11 | YACC rule #20 | YACC rule #10 YACC rule #819 YACC rule #11 | YACC rule #10 YACC rule #819 YACC rule #20 | YACC rule #10 YACC rule #819 this last fixes an erroneous start to a sentence, and permits incomplete JOIK_JEK after I, as well in answer to questions on those connectives ; statement_11 : YACC rule #12 | YACC rule #30 YACC rule #11 ; statement_A_12 : YACC rule #13 | YACC rule #12 YACC rule #820 YACC rule #13 | YACC rule #12 YACC rule #820 ; statement_B_13 : YACC rule #14 | YACC rule #14 YACC rule #811 YACC rule #13 | YACC rule #14 YACC rule #811 ; statement_C_14 : YACC rule #40 | YACC rule #447 YACC rule #2 YACC rule #454 | YACC rule #491 YACC rule #447 YACC rule #2 YACC rule #454 ; fragment_20 : YACC rule #802 | YACC rule #445 | YACC rule #818 | YACC rule #300 | YACC rule #80 YACC rule #456 answer to ma YACC rule #490 requires both YACC rule #450 and YACC rule #456 but needs no extra rule to accomplish this | YACC rule #121 | YACC rule #161 | YACC rule #160 | YACC rule #30 ; prenex_30 : YACC rule #80 YACC rule #492 ; free_modifier_32 : YACC rule #33 | YACC rule #33 YACC rule #32 ; free_modifier_A_33 : YACC rule #35 | YACC rule #36 | YACC rule #34 | YACC rule #486 | YACC rule #801 ; discursive_bridi_34 : YACC rule #440 YACC rule #130 YACC rule #459 | YACC rule #498 YACC rule #90 YACC rule #459 | YACC rule #498 YACC rule #90 YACC rule #90 YACC rule #459 | YACC rule #440 YACC rule #80 YACC rule #451 YACC rule #130 YACC rule #459 | YACC rule #440 YACC rule #80 YACC rule #130 YACC rule #459 ; vocative_35 : YACC rule #415 YACC rule #130 YACC rule #457 | YACC rule #415 YACC rule #130 YACC rule #121 YACC rule #457 | YACC rule #415 YACC rule #121 YACC rule #130 YACC rule #457 | YACC rule #415 YACC rule #121 YACC rule #130 YACC rule #121 YACC rule #457 | YACC rule #415 YACC rule #404 YACC rule #457 | YACC rule #415 YACC rule #404 YACC rule #121 YACC rule #457 | YACC rule #415 YACC rule #121 YACC rule #404 YACC rule #457 | YACC rule #415 YACC rule #121 YACC rule #404 YACC rule #121 YACC rule #457 | YACC rule #415 YACC rule #90 YACC rule #457 | YACC rule #415 YACC rule #457 ; parenthetical_36 : YACC rule #606 YACC rule #0 YACC rule #468 ; sentence_40 : YACC rule #50 bare observative or mo answer | YACC rule #80 YACC rule #451 YACC rule #50 | YACC rule #80 YACC rule #50 ; subsentence_41 : YACC rule #40 | YACC rule #30 YACC rule #41 ; bridi_tail_50 : YACC rule #51 | YACC rule #51 YACC rule #814 YACC rule #50 YACC rule #466 YACC rule #71 ; bridi_tail_A_51 : YACC rule #52 | YACC rule #51 YACC rule #818 YACC rule #52 YACC rule #71 ; bridi_tail_B_52 : YACC rule #53 | YACC rule #53 YACC rule #813 YACC rule #52 YACC rule #71 ; bridi_tail_C_53 : YACC rule #54 | YACC rule #130 YACC rule #71 ; gek_sentence_54 : YACC rule #807 YACC rule #41 YACC rule #816 YACC rule #41 YACC rule #71 | YACC rule #491 YACC rule #493 YACC rule #54 YACC rule #466 | YACC rule #445 YACC rule #54 ; tail_terms_71 : YACC rule #80 YACC rule #456 | YACC rule #456 ; terms_80 : YACC rule #81 | YACC rule #80 YACC rule #81 ; terms_A_81 : YACC rule #82 | YACC rule #81 YACC rule #494 YACC rule #422 YACC rule #82 ; terms_B_82 : YACC rule #83 | YACC rule #82 YACC rule #495 YACC rule #83 ; term_83 : YACC rule #90 | YACC rule #84 | YACC rule #85 | YACC rule #810 ; modifier_84 : YACC rule #490 YACC rule #450 | YACC rule #490 YACC rule #90 ; term_set_85 : YACC rule #496 YACC rule #80 YACC rule #460 | YACC rule #496 YACC rule #807 YACC rule #80 YACC rule #460 YACC rule #816 YACC rule #80 YACC rule #460 ; sumti_90 : YACC rule #91 | YACC rule #91 YACC rule #497 YACC rule #121 ; sumti_A_91 : YACC rule #92 | YACC rule #92 YACC rule #804 YACC rule #90 YACC rule #466 | YACC rule #92 YACC rule #823 YACC rule #90 YACC rule #466 ; sumti_B_92 : YACC rule #93 | YACC rule #92 YACC rule #421 YACC rule #93 ; sumti_C_93 : YACC rule #94 | YACC rule #94 YACC rule #803 YACC rule #93 | YACC rule #94 YACC rule #822 YACC rule #93 ; sumti_D_94 : YACC rule #95 | YACC rule #807 YACC rule #90 YACC rule #816 YACC rule #94 ; sumti_E_95 : YACC rule #96 | YACC rule #96 YACC rule #121 indefinite sumti | YACC rule #300 YACC rule #130 YACC rule #450 | YACC rule #300 YACC rule #130 YACC rule #450 YACC rule #121 ; sumti_F_96 : YACC rule #97 outer-quantified sumti | YACC rule #300 YACC rule #97 ; sumti_G_97 : YACC rule #483 YACC rule #90 YACC rule #463 | YACC rule #483 YACC rule #121 YACC rule #90 YACC rule #463 sumti grouping, set/mass/individual conversion; also sumti scalar negation | YACC rule #400 | YACC rule #499 YACC rule #404 | YACC rule #499 YACC rule #121 YACC rule #404 | YACC rule #489 YACC rule #310 YACC rule #472 | YACC rule #110 | YACC rule #432 ; description_110 : YACC rule #499 YACC rule #111 YACC rule #450 | YACC rule #488 YACC rule #111 YACC rule #450 ; sumti_tail_111 : YACC rule #112 inner-quantified sumti relative clause | YACC rule #121 YACC rule #112 pseudo-possessive (an abbreviated inner restriction); note that sumti cannot be quantified | YACC rule #97 YACC rule #112 pseudo-possessive with outer restriction | YACC rule #97 YACC rule #121 YACC rule #112 ; sumti_tail_A_112 : YACC rule #130 | YACC rule #130 YACC rule #121 explicit inner quantifier | YACC rule #300 YACC rule #130 quantifier both internal to a description, and external to a sumti thereby made specific | YACC rule #300 YACC rule #130 YACC rule #121 | YACC rule #300 YACC rule #90 ; relative_clauses_121 : YACC rule #122 | YACC rule #121 YACC rule #487 YACC rule #122 ; relative_clause_122 : YACC rule #485 YACC rule #83 YACC rule #464 | YACC rule #484 YACC rule #41 YACC rule #469 ; selbri_130 : YACC rule #491 YACC rule #131 | YACC rule #131 ; selbri_A_131 : YACC rule #132 | YACC rule #445 YACC rule #130 ; selbri_B_132 : YACC rule #133 | YACC rule #133 YACC rule #443 YACC rule #132 ; selbri_C_133 : YACC rule #134 | YACC rule #133 YACC rule #134 ; selbri_D_134 : YACC rule #135 | YACC rule #134 YACC rule #422 YACC rule #135 | YACC rule #134 YACC rule #823 YACC rule #133 YACC rule #466 ; selbri_E_135 : YACC rule #136 | YACC rule #136 YACC rule #821 YACC rule #135 | YACC rule #136 YACC rule #822 YACC rule #135 ; selbri_F_136 : YACC rule #150 | YACC rule #150 YACC rule #479 YACC rule #136 | YACC rule #137 | YACC rule #482 YACC rule #137 ; GUhEK_selbri_137 : YACC rule #808 YACC rule #130 YACC rule #816 YACC rule #136 ; tanru_unit_150 : YACC rule #151 | YACC rule #150 YACC rule #444 YACC rule #151 ; tanru_unit_A_151 : YACC rule #152 | YACC rule #152 YACC rule #160 ; tanru_unit_B_152 : YACC rule #407 | YACC rule #493 YACC rule #133 YACC rule #466 | YACC rule #480 YACC rule #152 | YACC rule #478 YACC rule #491 YACC rule #152 | YACC rule #478 YACC rule #152 | YACC rule #477 YACC rule #90 YACC rule #465 | YACC rule #477 YACC rule #90 YACC rule #465 YACC rule #476 | YACC rule #475 YACC rule #374 | YACC rule #482 YACC rule #152 | YACC rule #425 YACC rule #41 YACC rule #453 ; linkargs_160 : YACC rule #446 YACC rule #83 YACC rule #467 | YACC rule #446 YACC rule #83 YACC rule #161 YACC rule #467 ; links_161 : YACC rule #442 YACC rule #83 | YACC rule #442 YACC rule #83 YACC rule #161 ; Main entry point for MEX; everything but a number must be in parens. quantifier_300 : YACC rule #812 YACC rule #461 | YACC rule #470 YACC rule #310 YACC rule #471 ; Entry point for MEX used after LI; no parens needed, but LI now has an elidable terminator. (This allows us to express the difference between “the expression a + b” and “the expression (a + b)”) This rule supports left-grouping infix expressions and reverse Polish expressions. To handle infix monadic, use a null operand; to handle infix with more than two operands (whatever that means) use an extra operator or an array operand. MEX_310 : YACC rule #311 | YACC rule #310 YACC rule #370 YACC rule #311 | YACC rule #441 YACC rule #330 ; Support for right-grouping (short scope) infix expressions with BIhE. MEX_A_311 : YACC rule #312 | YACC rule #312 YACC rule #439 YACC rule #370 YACC rule #311 ; Support for forethought (Polish) expressions. These begin with a forethought flag, then the operator and then the argument(s). MEX_B_312 : YACC rule #381 | YACC rule #370 YACC rule #313 YACC rule #452 | YACC rule #438 YACC rule #370 YACC rule #313 YACC rule #452 ; MEX_C_313 : YACC rule #312 | YACC rule #313 YACC rule #312 ; Reverse Polish expressions always have exactly two operands. To handle one operand, use a null operand; to handle more than two operands, use a null operator. rp_expression_330 : YACC rule #332 YACC rule #332 YACC rule #370 ; rp_operand_332 : YACC rule #381 | YACC rule #330 ; Operators may be joined by logical connectives. operator_370 : YACC rule #371 | YACC rule #370 YACC rule #422 YACC rule #371 | YACC rule #370 YACC rule #823 YACC rule #370 YACC rule #466 ; operator_A_371 : YACC rule #372 | YACC rule #808 YACC rule #371 YACC rule #816 YACC rule #372 | YACC rule #372 YACC rule #822 YACC rule #371 | YACC rule #372 YACC rule #821 YACC rule #371 ; operator_B_372 : YACC rule #374 | YACC rule #493 YACC rule #370 YACC rule #466 ; MEX_operator_374 : YACC rule #679 | YACC rule #679 YACC rule #32 | YACC rule #480 YACC rule #374 changes argument order | YACC rule #482 YACC rule #374 scalar negation | YACC rule #430 YACC rule #310 YACC rule #473 | YACC rule #429 YACC rule #130 YACC rule #473 ; operand_381 : YACC rule #382 | YACC rule #382 YACC rule #804 YACC rule #381 YACC rule #466 | YACC rule #382 YACC rule #823 YACC rule #381 YACC rule #466 ; operand_A_382 : YACC rule #383 | YACC rule #382 YACC rule #421 YACC rule #383 ; operand_B_383 : YACC rule #385 | YACC rule #385 YACC rule #803 YACC rule #383 | YACC rule #385 YACC rule #822 YACC rule #383 ; operand_C_385 : YACC rule #300 | YACC rule #817 YACC rule #461 lerfu string as operand – classic math variable | YACC rule #428 YACC rule #130 YACC rule #473 quantifies a bridi – inverse of -MOI | YACC rule #427 YACC rule #90 YACC rule #473 quantifies a sumti – inverse of LI | YACC rule #431 YACC rule #313 YACC rule #473 | YACC rule #807 YACC rule #381 YACC rule #816 YACC rule #385 | YACC rule #483 YACC rule #381 YACC rule #463 ; _400 series constructs are mostly specific strings, some of which may also be used by the lexer; the lexer should not use any reference to terminals numbered less than _400, as they have grammars composed on non-deterministic strings of selma'o. Some above _400 also are this way, so care should be taken; this is especially true for those that reference YACC rule #32. anaphora_400 : YACC rule #555 | YACC rule #555 YACC rule #32 | YACC rule #817 YACC rule #461 ; cmevla_404 : YACC rule #405 | YACC rule #405 YACC rule #32 ; cmevla_A_405 : YACC rule #518 pause | YACC rule #405 YACC rule #518 pause multiple CMEVLA are identified morphologically (by the lexer) - - separated by consonant & pause ; bridi_valsi_407 : YACC rule #408 | YACC rule #408 YACC rule #32 ; bridi_valsi_A_408 : YACC rule #509 | YACC rule #824 | YACC rule #543 | YACC rule #543 YACC rule #593 ; para_mark_410 : YACC rule #584 | YACC rule #584 YACC rule #32 | YACC rule #584 YACC rule #410 ; indicators_411 : YACC rule #412 | YACC rule #535 YACC rule #412 ; indicators_A_412 : YACC rule #413 | YACC rule #412 YACC rule #413 ; indicator_413 : YACC rule #612 | YACC rule #515 | YACC rule #612 YACC rule #581 | YACC rule #515 YACC rule #581 | YACC rule #619 | YACC rule #524 | YACC rule #536 ; DOI_415 : YACC rule #525 | YACC rule #416 | YACC rule #416 YACC rule #525 ; COI_416 : YACC rule #417 | YACC rule #416 YACC rule #417 ; COI_A_417 : YACC rule #520 | YACC rule #520 YACC rule #581 ; JOIK_EK_421 : YACC rule #802 | YACC rule #806 | YACC rule #806 YACC rule #32 ; JOIK_JEK_422 : YACC rule #806 | YACC rule #806 YACC rule #32 | YACC rule #805 | YACC rule #805 YACC rule #32 ; XI_424 : YACC rule #618 | YACC rule #618 YACC rule #32 ; NU_425 : YACC rule #426 | YACC rule #425 YACC rule #422 YACC rule #426 ; NU_A_426 : YACC rule #586 | YACC rule #586 YACC rule #581 | YACC rule #586 YACC rule #32 | YACC rule #586 YACC rule #581 YACC rule #32 ; MOhE_427 : YACC rule #664 | YACC rule #664 YACC rule #32 ; NIhE_428 : YACC rule #666 | YACC rule #666 YACC rule #32 ; NAhU_429 : YACC rule #665 | YACC rule #665 YACC rule #32 ; MAhO_430 : YACC rule #662 | YACC rule #662 YACC rule #32 ; JOhI_431 : YACC rule #657 | YACC rule #657 YACC rule #32 ; quote_arg_432 : YACC rule #433 | YACC rule #433 YACC rule #32 ; quote_arg_A_433 : YACC rule #434 | YACC rule #435 | YACC rule #436 | YACC rule #571 YACC rule #0 YACC rule #448 ; The quoted material in the following three terminals must be identified by the lexer, but no additional lexer processing is needed. ZOI_quote_434 : YACC rule #627 YACC rule #698 pause YACC rule #699 pause YACC rule #698 ; “pause” is morphemic, represented by . The lexer assembles YACC rule #699 ZO_quote_435 : YACC rule #626 YACC rule #698 ; “word” may not be a compound; but it can be any valid Lojban selma'o value, including ZO, ZOI, SI, SA, SU. The preparser will not lex the word per its normal selma'o. LOhU_quote_436 : YACC rule #569 YACC rule #697 YACC rule #565 ; “words” may be any Lojban words, with no claim of grammaticality; the preparser will not lex the individual words per their normal selma'o; used to quote ungrammatical Lojban, equivalent to the * or ? writing convention for such text. The preparser needs one bit of sophistication for this rule. A quoted string should be able to contain other quoted strings – this is only a problem for a LOhU quote itself, since the LEhU clossing this quote would otherwise close the outer quotes, which is incorrect. For this purpose, we will cheat on the use of ZO in such a quote (since this is ungrammatical text, it is a sign ignored by the parser). Use ZO to mark any nested quotation LOhU. The preparser then will absorb it by the ZO rule, before testing for LOhU. This is obviously not the standard usage for ZO, which would otherwise cause the result to be a sumti. But, since the result will be part of an unparsed string anyway, it doesn't matter. It may be seen that any of the ZO/ZOI/LOhU trio of quotation markers may contain the powerful metalinguistic erasers. Since these quotations are not parsed internally, these operators are ignored within the quote. To erase a ZO, then, two SI's are needed after giving a quoted word of any type. ZOI takes four SI's, with the ENTIRE BODY OF THE QUOTE treated as a single “word” since it is one selma'o. Thus one for the quote body, two for the single word delimiters, and one for the ZOI. In LOhU, the entire body is treated as a single word, so three SI's can erase it. All rule terminator names with “gap” in them are potentially elidable, where such elision does not cause an ambiguity. This is implemented through use of the YACC “error” token, which effectively recovers from an elision. FIhO_437 : YACC rule #532 | YACC rule #532 YACC rule #32 ; PEhO_438 : YACC rule #673 | YACC rule #673 YACC rule #32 ; BIhE_439 : YACC rule #650 | YACC rule #650 YACC rule #32 ; SEI_440 : YACC rule #597 | YACC rule #597 YACC rule #32 ; FUhA_441 : YACC rule #655 | YACC rule #655 YACC rule #32 ; BEI_442 : YACC rule #505 | YACC rule #505 YACC rule #32 ; CO_443 : YACC rule #519 | YACC rule #519 YACC rule #32 ; CEI_444 : YACC rule #516 | YACC rule #516 YACC rule #32 ; NA_445 : YACC rule #578 | YACC rule #578 YACC rule #32 ; BE_446 : YACC rule #504 | YACC rule #504 YACC rule #32 ; TUhE_447 : YACC rule #610 | YACC rule #610 YACC rule #32 ; LIhU_gap_448 : YACC rule #567 | error ; gap_450 : YACC rule #556 | YACC rule #556 YACC rule #32 | error ; front_gap_451 : YACC rule #521 | YACC rule #521 YACC rule #32 ; MEX_gap_452 : YACC rule #658 | YACC rule #658 YACC rule #32 | error ; KEI_gap_453 : YACC rule #552 | YACC rule #552 YACC rule #32 | error ; TUhU_gap_454 : YACC rule #611 | YACC rule #611 YACC rule #32 | error ; VAU_gap_456 : YACC rule #614 | YACC rule #614 YACC rule #32 | error ; redundant to attach a free modifier on the following DOhU_gap_457 : YACC rule #526 | error ; FEhU_gap_458 : YACC rule #531 | YACC rule #531 YACC rule #32 | error ; SEhU_gap_459 : YACC rule #598 | error a free modifier on a discursive should be somewhere within the discursive. See YACC rule #440 ; NUhU_gap_460 : YACC rule #588 | YACC rule #588 YACC rule #32 | error ; BOI_gap_461 : YACC rule #651 | YACC rule #651 YACC rule #32 | error ; sub_gap_462 : YACC rule #651 | error ; LUhU_gap_463 : YACC rule #573 | YACC rule #573 YACC rule #32 | error ; GEhU_gap_464 : YACC rule #538 | YACC rule #538 YACC rule #32 | error ; MEhU_gap_465 : YACC rule #575 | YACC rule #575 YACC rule #32 | error ; KEhE_gap_466 : YACC rule #550 | YACC rule #550 YACC rule #32 | error ; BEhO_gap_467 : YACC rule #506 | YACC rule #506 YACC rule #32 | error ; TOI_gap_468 : YACC rule #607 | error ; KUhO_gap_469 : YACC rule #557 | YACC rule #557 YACC rule #32 | error ; left_bracket_470 : YACC rule #677 | YACC rule #677 YACC rule #32 ; right_bracket_gap_471 : YACC rule #678 | YACC rule #678 YACC rule #32 | error ; LOhO_gap_472 : YACC rule #568 | YACC rule #568 YACC rule #32 | error ; TEhU_gap_473 : YACC rule #675 | YACC rule #675 YACC rule #32 | error ; right_br_no_free_474 : YACC rule #678 | error ; NUhA_475 : YACC rule #667 | YACC rule #667 YACC rule #32 ; MOI_476 : YACC rule #663 | YACC rule #663 YACC rule #32 ; ME_477 : YACC rule #574 | YACC rule #574 YACC rule #32 ; JAI_478 : YACC rule #547 | YACC rule #547 YACC rule #32 ; BO_479 : YACC rule #508 | YACC rule #508 YACC rule #32 ; SE_480 : YACC rule #596 | YACC rule #596 YACC rule #32 ; FA_481 : YACC rule #527 | YACC rule #527 YACC rule #32 ; NAhE_482 : YACC rule #583 | YACC rule #583 YACC rule #32 ; qualifier_483 : YACC rule #561 | YACC rule #561 YACC rule #32 | YACC rule #809 ; NOI_484 : YACC rule #585 | YACC rule #585 YACC rule #32 ; GOI_485 : YACC rule #542 | YACC rule #542 YACC rule #32 ; subscript_486 : YACC rule #424 YACC rule #812 YACC rule #462 | YACC rule #424 YACC rule #470 YACC rule #310 YACC rule #474 | YACC rule #424 YACC rule #817 YACC rule #462 ; ZIhE_487 : YACC rule #625 | YACC rule #625 YACC rule #32 ; LE_488 : YACC rule #562 | YACC rule #562 YACC rule #32 ; LI_489 : YACC rule #566 | YACC rule #566 YACC rule #32 ; mod_head_490 : YACC rule #491 | YACC rule #481 ; tag_491 : YACC rule #815 | YACC rule #491 YACC rule #422 YACC rule #815 ; ZOhU_492 : YACC rule #628 | YACC rule #628 YACC rule #32 ; KE_493 : YACC rule #551 | YACC rule #551 YACC rule #32 ; PEhE_494 : YACC rule #591 | YACC rule #591 YACC rule #32 ; CEhE_495 : YACC rule #517 | YACC rule #517 YACC rule #32 ; NUhI_496 : YACC rule #587 | YACC rule #587 YACC rule #32 ; VUhO_497 : YACC rule #617 | YACC rule #617 YACC rule #32 ; SOI_498 : YACC rule #602 | YACC rule #602 YACC rule #32 ; LA_499 : YACC rule #558 | YACC rule #558 YACC rule #32 ; utterance_ordinal_801 : YACC rule #905 ; EK_802 : YACC rule #910 | YACC rule #910 YACC rule #32 ; EK_BO_803 : YACC rule #915 | YACC rule #915 YACC rule #32 ; EK_KE_804 : YACC rule #916 | YACC rule #916 YACC rule #32 ; JEK_805 : YACC rule #925 ; JOIK_806 : YACC rule #930 ; GEK_807 : YACC rule #935 | YACC rule #935 YACC rule #32 ; GUhEK_808 : YACC rule #940 | YACC rule #940 YACC rule #32 ; NAhE_BO_809 : YACC rule #945 | YACC rule #945 YACC rule #32 ; NA_KU_810 : YACC rule #950 | YACC rule #950 YACC rule #32 ; I_BO_811 : YACC rule #955 | YACC rule #955 YACC rule #32 ; number_812 : YACC rule #960 ; GIhEK_BO_813 : YACC rule #965 | YACC rule #965 YACC rule #32 ; GIhEK_KE_814 : YACC rule #966 | YACC rule #966 YACC rule #32 ; tense_modal_815 : YACC rule #970 | YACC rule #970 YACC rule #32 | YACC rule #437 YACC rule #130 YACC rule #458 ; GIK_816 : YACC rule #980 | YACC rule #980 YACC rule #32 ; lerfu_string_817 : YACC rule #985 ; GIhEK_818 : YACC rule #990 | YACC rule #990 YACC rule #32 ; I_819 : YACC rule #995 | YACC rule #995 YACC rule #32 ; I_JEK_820 : YACC rule #1000 | YACC rule #1000 YACC rule #32 ; JEK_BO_821 : YACC rule #1005 | YACC rule #1005 YACC rule #32 ; JOIK_BO_822 : YACC rule #1010 | YACC rule #1010 YACC rule #32 ; JOIK_KE_823 : YACC rule #1015 | YACC rule #1015 YACC rule #32 ; PA_MOI_824 : YACC rule #1025 ; The following rules are used only in lexer processing. They have been tested for ambiguity at various levels in the YACC grammar, but are in the recursive descent lexer in the current parser. The lexer inserts the lexer tokens before the processed strings, but leaves the original tokens. lexer_A_905 : YACC rule #701 YACC rule #906 ; utt_ordinal_root_906 : YACC rule #986 YACC rule #661 | YACC rule #961 YACC rule #661 ; lexer_B_910 : YACC rule #702 YACC rule #911 ; EK_root_911 : YACC rule #501 | YACC rule #596 YACC rule #501 | YACC rule #578 YACC rule #501 | YACC rule #501 YACC rule #581 | YACC rule #596 YACC rule #501 YACC rule #581 | YACC rule #578 YACC rule #501 YACC rule #581 | YACC rule #578 YACC rule #596 YACC rule #501 | YACC rule #578 YACC rule #596 YACC rule #501 YACC rule #581 ; lexer_C_915 : YACC rule #703 YACC rule #911 YACC rule #508 | YACC rule #703 YACC rule #911 YACC rule #971 YACC rule #508 ; lexer_D_916 : YACC rule #704 YACC rule #911 YACC rule #551 | YACC rule #704 YACC rule #911 YACC rule #971 YACC rule #551 ; lexer_E_925 : YACC rule #705 YACC rule #926 ; JEK_root_926 : YACC rule #546 | YACC rule #546 YACC rule #581 | YACC rule #578 YACC rule #546 | YACC rule #578 YACC rule #546 YACC rule #581 | YACC rule #596 YACC rule #546 | YACC rule #596 YACC rule #546 YACC rule #581 | YACC rule #578 YACC rule #596 YACC rule #546 | YACC rule #578 YACC rule #596 YACC rule #546 YACC rule #581 ; lexer_F_930 : YACC rule #706 YACC rule #931 ; JOIK_root_931 : YACC rule #548 | YACC rule #548 YACC rule #581 | YACC rule #596 YACC rule #548 | YACC rule #596 YACC rule #548 YACC rule #581 | YACC rule #932 | YACC rule #656 YACC rule #932 YACC rule #656 ; interval_932 : YACC rule #507 | YACC rule #507 YACC rule #581 | YACC rule #596 YACC rule #507 | YACC rule #596 YACC rule #507 YACC rule #581 ; lexer_G_935 : YACC rule #707 YACC rule #537 | YACC rule #707 YACC rule #596 YACC rule #537 | YACC rule #707 YACC rule #537 YACC rule #581 | YACC rule #707 YACC rule #596 YACC rule #537 YACC rule #581 | YACC rule #707 YACC rule #971 YACC rule #981 | YACC rule #707 YACC rule #931 YACC rule #539 ; lexer_H_940 : YACC rule #708 YACC rule #544 | YACC rule #708 YACC rule #596 YACC rule #544 | YACC rule #708 YACC rule #544 YACC rule #581 | YACC rule #708 YACC rule #596 YACC rule #544 YACC rule #581 ; lexer_I_945 : YACC rule #709 YACC rule #583 YACC rule #508 ; lexer_J_950 : YACC rule #710 YACC rule #578 YACC rule #556 ; lexer_K_955 : YACC rule #711 YACC rule #956 YACC rule #508 | YACC rule #711 YACC rule #956 YACC rule #971 YACC rule #508 ; I_root_956 : YACC rule #545 | YACC rule #545 YACC rule #957 ; simple_JOIK_JEK_957 : YACC rule #806 | YACC rule #805 ; no freemod in this version; cf. YACC rule #422 this reference to a version of JOIK and JEK which already have the lexer tokens attached prevents shift/reduce errors. The problem is resolved in a hard-coded parser implementation which builds lexer_K, before lexer_S, before lexer_E and lexer_F. lexer_L_960 : YACC rule #712 YACC rule #961 ; number_root_961 : YACC rule #672 | YACC rule #961 YACC rule #672 | YACC rule #961 YACC rule #987 ; lexer_M_965 : YACC rule #713 YACC rule #991 YACC rule #508 | YACC rule #713 YACC rule #991 YACC rule #971 YACC rule #508 ; lexer_N_966 : YACC rule #714 YACC rule #991 YACC rule #551 | YACC rule #714 YACC rule #991 YACC rule #971 YACC rule #551 ; lexer_O_970 : YACC rule #715 YACC rule #972 ; the following rule is a lexer version of non-terminal_815 for compounding PU/modals; it disallows the lexer picking out FIhO clauses, which would require it to have knowledge of the main parser grammar simple_tag_971 : YACC rule #972 | YACC rule #971 YACC rule #957 YACC rule #972 ; simple_tense_modal_972 : YACC rule #973 | YACC rule #583 YACC rule #973 | YACC rule #554 | YACC rule #522 ; simple_tense_modal_A_973: YACC rule #974 | YACC rule #974 YACC rule #554 | YACC rule #977 ; modal_974 : YACC rule #975 | YACC rule #975 YACC rule #581 ; modal_A_975 : YACC rule #502 | YACC rule #596 YACC rule #502 ; tense_A_977 : YACC rule #978 | YACC rule #978 YACC rule #554 ; tense_B_978 : YACC rule #979 | YACC rule #514 | YACC rule #979 YACC rule #514 ; specifies actuality/potentiality of the bridi puca'a = actually was baca'a = actually will be bapu'i = can and will have banu'o = can, but won't have yet canu'ojebapu'i = can, hasn't yet, but will tense_C_979 : YACC rule #1030 time-only space defaults to time-space reference space | YACC rule #1040 can include time if specified with VIhA; otherwise time defaults to the time-space reference time | YACC rule #1030 YACC rule #1040 time and space – If YACC rule #1040 is marked with VIhA for space-time the tense may be self-contradictory interval prop before space_time is for time distribution | YACC rule #1040 YACC rule #1030 ; lexer_P_980 : YACC rule #716 YACC rule #981 ; GIK_root_981 : YACC rule #539 | YACC rule #539 YACC rule #581 ; lexer_Q_985 : YACC rule #717 YACC rule #986 ; lerfu_string_root_986 : YACC rule #987 | YACC rule #986 YACC rule #987 | YACC rule #986 YACC rule #672 ; lerfu_word_987 : YACC rule #513 | YACC rule #559 YACC rule #987 | YACC rule #605 YACC rule #986 YACC rule #533 ; lexer_R_990 : YACC rule #718 YACC rule #991 ; GIhEK_root_991 : YACC rule #541 | YACC rule #596 YACC rule #541 | YACC rule #578 YACC rule #541 | YACC rule #541 YACC rule #581 | YACC rule #596 YACC rule #541 YACC rule #581 | YACC rule #578 YACC rule #541 YACC rule #581 | YACC rule #578 YACC rule #596 YACC rule #541 | YACC rule #578 YACC rule #596 YACC rule #541 YACC rule #581 ; lexer_S_995 : YACC rule #719 YACC rule #545 ; lexer_T_1000 : YACC rule #720 YACC rule #545 YACC rule #957 ; lexer_U_1005 : YACC rule #721 YACC rule #926 YACC rule #508 | YACC rule #721 YACC rule #926 YACC rule #971 YACC rule #508 ; lexer_V_1010 : YACC rule #722 YACC rule #931 YACC rule #508 | YACC rule #722 YACC rule #931 YACC rule #971 YACC rule #508 ; lexer_W_1015 : YACC rule #723 YACC rule #931 YACC rule #551 | YACC rule #723 YACC rule #931 YACC rule #971 YACC rule #551 ; lexer_Y_1025 : YACC rule #725 YACC rule #961 YACC rule #663 | YACC rule #725 YACC rule #986 YACC rule #663 ; time_1030 : YACC rule #624 | YACC rule #624 YACC rule #1031 | YACC rule #1031 ; time_A_1031 : YACC rule #1032 | YACC rule #1034 | YACC rule #1032 YACC rule #1034 ; time_B_1032 : YACC rule #1033 | YACC rule #1032 YACC rule #1033 ; time_offset_1033 : YACC rule #1035 | YACC rule #1035 YACC rule #624 ; time_interval_1034 : YACC rule #622 | YACC rule #622 YACC rule #1035 | YACC rule #1036 | YACC rule #622 YACC rule #1036 | YACC rule #622 YACC rule #1035 YACC rule #1036 ; time_direction_1035 : YACC rule #592 | YACC rule #592 YACC rule #581 ; time_int_props_1036 : YACC rule #1051 | YACC rule #1036 YACC rule #1051 ; space_1040 : YACC rule #1042 | YACC rule #1041 | YACC rule #1042 YACC rule #1041 ; space_motion_1041 : YACC rule #577 YACC rule #1045 ; space_A_1042 : YACC rule #613 | YACC rule #613 YACC rule #1043 | YACC rule #1043 ; space_B_1043 : YACC rule #1044 | YACC rule #1046 | YACC rule #1044 YACC rule #1046 ; space_C_1044 : YACC rule #1045 | YACC rule #1044 YACC rule #1045 ; space_offset_1045 : YACC rule #1048 | YACC rule #1048 YACC rule #613 ; space_intval_1046 : YACC rule #1047 | YACC rule #1047 YACC rule #1048 | YACC rule #1049 | YACC rule #1047 YACC rule #1049 | YACC rule #1047 YACC rule #1048 YACC rule #1049 ; space_intval_A_1047 : YACC rule #615 | YACC rule #616 | YACC rule #615 YACC rule #616 ; space_direction_1048 : YACC rule #528 | YACC rule #528 YACC rule #581 ; space_int_props_1049 : YACC rule #1050 | YACC rule #1049 YACC rule #1050 ; space_int_props_A_1050 : YACC rule #530 YACC rule #1051 ; This terminal gives an interval size in space-time (VEhA), and possibly a dimensionality of the interval. The dimensionality may also be used with the interval size left unspecified. When this terminal is used for the spacetime origin, then barring any overriding VIhA, a VIhA here defines the dimensionality of the space-time being discussed. interval_property_1051 : YACC rule #961 YACC rule #594 | YACC rule #961 YACC rule #594 YACC rule #581 | YACC rule #604 | YACC rule #604 YACC rule #581 | YACC rule #621 | YACC rule #621 YACC rule #581 ; extensional/intensional interval parameters These may be appended to any defined interval, or may stand in place of either time or space tenses. If no other tense is present, this terminal stands for the time-space interval parameter with an unspecified interval. roroi = always and everywhere roroiku'avi = always here (ku'a = intersection) puroroi = always in the past paroi = once upon a time (somewhere) paroiku'avi = once upon a time here The following are “Lexer-only rules”, covered by steps 1-4 described at the beginning. The grammar of these constructs is nonexistent, except possibly in cases where they interact with each other. Even there, however, the effects are semantic rather than grammatical. Where it is believed possible that conflicts could exist, the grammar of these constructs has been put in the above grammar, even though the lexer/Preparser will actually prevent these from being passed thru to the parse routine. (Otherwise we have to put unacceptably fancy code in the PreParser to determine just when these can be passed thru, and when they can't.) Constructs in this category include quotes and indicators as defined above. (The above grammar handles utterance scope (free_modifier) and clause scope (gap) applications of the latter, however, and indicators should be allowed to be absorbed into almost any word without changing its grammar. YACC rule #601, YACC rule #595, and YACC rule #603 are metalinguistic erasers. token_1100 : YACC rule #698 | YACC rule #503 YACC rule #698 | YACC rule #699 | YACC rule #698 YACC rule #511 | YACC rule #698 YACC rule #524 | YACC rule #698 YACC rule #536 | YACC rule #698 YACC rule #535 | YACC rule #698 YACC rule #612 | YACC rule #698 YACC rule #612 YACC rule #581 | YACC rule #698 YACC rule #619 | YACC rule #698 YACC rule #515 | YACC rule #698 YACC rule #515 YACC rule #581 | YACC rule #612 YACC rule #581 | YACC rule #515 YACC rule #581 ; null_1101 : YACC rule #698 YACC rule #601 | possibly_unlexable_word (PAUSE) YACC rule #601 | YACC rule #20 YACC rule #595 | possibly unlexable string (PAUSE) YACC rule #595 erases back to the last individual token I or NIhO or start of text, ignoring the insides of ZOI, ZO, and LOhU/LEhU quotes. Start of text is defined for SU below. | YACC rule #3 YACC rule #603 | possibly unparsable text (PAUSE) YACC rule #603 erases back to start of text which is the beginning of a speaker's statement, a parenthesis (TO/TOI), a LU/LIhU quote, or a TUhE/TUhU utterance string. ; %%
Lojban Machine Grammar, EBNF Version, Final Baseline
This EBNF document is explicitly dedicated to the public domain by its author, The Logical Language Group, Inc. Contact that organization at: 2904 Beau Lane, Fairfax VA 22031 USA 703-385-0273 (intl: +1 703 385 0273)
Explanation of notation: All rules have the form:
name number = bnf-expression
which means that the grammatical construct “name” is defined by “bnf-expression”.
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Names in lower case are grammatical constructs.
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Names in UPPER CASE are selma'o (lexeme) names, and are terminals.
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Concatenation is expressed by juxtaposition with no operator symbol.
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| represents alternation (choice).
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[] represents an optional element.
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& represents and/or. “A & B” is the same as “A | B | A B” but not “B A”. Furthermore, “A & B & C & D” permits one or more of A, B, C, and/or D, but only in that order.
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... represents optional repetition of the construct to the left. Left-grouping is implied; right-grouping is shown by explicit self-referential recursion with no “...”
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() serves to indicate the grouping of the other operators. Otherwise, “...” binds closer than &, which binds closer than |.
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# is shorthand for “[free ...]” , a construct which appears in many places.
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// encloses an elidable terminator, which may be omitted (without change of meaning) if no grammatical ambiguity results.
- text 0 =
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[NAI ...] [CMEVLA ... # | (indicators & free ...)] [joik-jek] text-1
- text-1 2 =
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[(I [jek | joik] [[stag] BO] #) ... | NIhO ... #] [paragraphs]
- paragraphs 4 =
- paragraph 10 =
- statement 11 =
- statement-1 12 =
- statement-2 13 =
- statement-3 14 =
- fragment 20 =
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ek # | gihek # | quantifier | NA # | terms /VAU#/ | prenex | relative-clauses | links | linkargs
- prenex 30 =
- sentence 40 =
- subsentence 41 =
- bridi-tail 50 =
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bridi-tail-1 [gihek [stag] KE # bridi-tail /KEhE#/ tail-terms]
- bridi-tail-1 51 =
- bridi-tail-2 52 =
- bridi-tail-3 53 =
- gek-sentence 54 =
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gek subsentence gik subsentence tail-terms | [tag] KE # gek-sentence /KEhE#/ | NA # gek-sentence
- tail-terms 71 =
- terms 80 =
- terms-1 81 =
- terms-2 82 =
- term 83 =
- termset 85 =
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NUhI # gek terms /NUhU#/ gik terms /NUhU#/ | NUhI # terms /NUhU#/
- sumti 90 =
- sumti-1 91 =
- sumti-2 92 =
- sumti-3 93 =
- sumti-4 94 =
- sumti-5 95 =
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[quantifier] sumti-6 [relative-clauses] | quantifier selbri /KU#/ [relative-clauses]
- sumti-6 97 =
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(LAhE # | NAhE BO #) [relative-clauses] sumti /LUhU#/ | KOhA # | lerfu-string /BOI#/ | LA # [relative-clauses] CMEVLA ... # | (LA | LE) # sumti-tail /KU#/ | LI # mex /LOhO#/ | ZO any-word # | LU text /LIhU#/ | LOhU any-word ... LEhU # | ZOI any-word anything any-word #
- sumti-tail 111 =
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[sumti-6 [relative-clauses]] sumti-tail-1 | relative-clauses sumti-tail-1
- sumti-tail-1 112 =
- relative-clauses 121 =
- relative-clause 122 =
- selbri 130 =
- selbri-1 131 =
- selbri-2 132 =
- selbri-3 133 =
- selbri-4 134 =
-
selbri-5 [joik-jek selbri-5 | joik [stag] KE # selbri-3 /KEhE#/] ...
- selbri-5 135 =
- selbri-6 136 =
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tanru-unit [BO # selbri-6] | [NAhE #] guhek selbri gik selbri-6
- tanru-unit 150 =
- tanru-unit-1 151 =
- tanru-unit-2 152 =
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BRIVLA # | GOhA [RAhO] # | KE # selbri-3 /KEhE#/ | ME # sumti /MEhU#/ [MOI #] | (number | lerfu-string) MOI # | NUhA # mex-operator | SE # tanru-unit-2 | JAI # [tag] tanru-unit-2 | any-word (ZEI any-word) ... | NAhE # tanru-unit-2 | NU [NAI] # [joik-jek NU [NAI] #] ... subsentence /KEI#/
- linkargs 160 =
- links 161 =
- quantifier 300 =
- mex 310 =
- mex-1 311 =
- mex-2 312 =
- rp-expression 330 =
- rp-operand 332 =
- operator 370 =
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operator-1 [joik-jek operator-1 | joik [stag] KE # operator /KEhE#/] ...
- operator-1 371 =
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operator-2 | guhek operator-1 gik operator-2 | operator-2 (jek | joik) [stag] BO # operator-1
- operator-2 372 =
- mex-operator 374 =
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SE # mex-operator | NAhE # mex-operator | MAhO # mex /TEhU#/ | NAhU # selbri /TEhU#/ | VUhU #
- operand 381 =
- operand-1 382 =
- operand-2 383 =
- operand-3 385 =
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quantifier | lerfu-string /BOI#/ | NIhE # selbri /TEhU#/ | MOhE # sumti /TEhU#/ | JOhI # mex-2 ... /TEhU#/ | gek operand gik operand-3 | (LAhE # | NAhE BO #) operand /LUhU#/
- number 812 =
- lerfu-string 817 =
- lerfu-word 987 =
- ek 802 =
- gihek 818 =
- jek 805 =
- joik 806 =
- interval 932 =
- joik-ek 421 =
- joik-jek 422 =
- gek 807 =
- guhek 808 =
- gik 816 =
- tag 491 =
- stag 971 =
- tense-modal 815 =
- simple-tense-modal 972 =
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[NAhE] [SE] BAI [NAI] [KI] | [NAhE] (time [space] | space [time]) & CAhA [KI] | KI | CUhE
- time 1030 =
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ZI & time-offset ... & (ZEhA [PU [NAI]]) & interval-property ...
- time-offset 1033 =
- space 1040 =
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VA & space-offset ... & space-interval & (MOhI space-offset)
- space-offset 1045 =
- space-interval 1046 =
- space-int-props 1049 =
- interval-property 1051 =
- free 32 =
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SEI # [terms [CU #]] selbri /SEhU/ | SOI # sumti [sumti] /SEhU/ | vocative [relative-clauses] selbri [relative-clauses] /DOhU/ | vocative [relative-clauses] CMEVLA ... # [relative-clauses] /DOhU/ | vocative [sumti] /DOhU/ | (number | lerfu-string) MAI | TO text /TOI/ | XI # (number | lerfu-string) /BOI/ | XI # VEI # mex /VEhO/
- vocative 415 =
- indicators 411 =
- indicator 413 =
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(UI | CAI) [NAI] | Y | DAhO | FUhO
The following rules are non-formal:
FAhO is a universal terminator and signals the end of parsable input.