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tptp_v7_0_0_0.g4
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tptp_v7_0_0_0.g4
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// created by Alexander Steen ([email protected])
// and Tobias Gleißner ([email protected])
// #INFO is about sections or where the parse tree has been flattened according to ANTLR idiomatics
// #ALT alternative grammar formulation for some parts
// #RES where no further restrictions are applied e.g. in the case of defined_functor
// any dollar word is allowed instead of only the predefined functors
grammar tptp_v7_0_0_0;
// #INFO HERE COME THE LEXER RULES
fragment Do_char : [\u0020-\u0021\u0023-\u005B\u005D-\u007E] | '\\'["\\];
fragment Sq_char : [\u0020-\u0026\u0028-\u005B\u005D-\u007E] | '\\'['\\];
fragment Sign : [+-];
fragment Exponent : [Ee];
fragment Non_zero_numeric : [1-9];
fragment Numeric : [0-9];
fragment Lower_alpha : [a-z];
fragment Upper_alpha : [A-Z];
fragment Alpha_numeric : Lower_alpha | Upper_alpha | Numeric | '_';
Or: '|';
And: '&';
Iff : '<=>';
Impl : '=>';
If: '<=';
Niff: '<~>';
Nor: '~|';
Nand: '~&';
Not: '~';
ForallComb: '!!';
TyForall: '!>';
Infix_inequality : '!=';
Infix_equality : '=';
Forall: '!';
ExistsComb: '??';
TyExists: '?*';
Exists: '?';
Lambda: '^';
ChoiceComb: '@@+';
Choice: '@+';
DescriptionComb: '@@-';
Description: '@-';
EqComb: '@=';
App: '@';
Assignment: ':=';
Arrow: '>';
Star: '*';
Plus: '+';
Subtype_sign: '<<';
Gentzen_arrow : '-->';
Real : Signed_real | Unsigned_real;
Signed_real : Sign Unsigned_real;
Unsigned_real : Decimal_fraction|Decimal_exponent;
Rational: Signed_rational | Unsigned_rational;
Signed_rational: Sign Unsigned_rational;
Unsigned_rational: Decimal '/' Positive_decimal;
Integer : Signed_integer | Unsigned_integer;
Signed_integer: Sign Unsigned_integer;
Unsigned_integer: Decimal;
Decimal : '0' | Positive_decimal;
Positive_decimal : Non_zero_numeric Numeric*;
Decimal_exponent : (Decimal|Decimal_fraction) Exponent Exp_integer;
Decimal_fraction : Decimal Dot_decimal;
Dot_decimal : '.' Numeric Numeric*;
Exp_integer : Signed_exp_integer|Unsigned_exp_integer;
Signed_exp_integer : Sign Unsigned_exp_integer;
Unsigned_exp_integer : Numeric Numeric*;
Dollar_word : '$' Lower_word;
Dollar_dollar_word : '$$' Lower_word;
Upper_word : Upper_alpha Alpha_numeric*;
Lower_word : Lower_alpha Alpha_numeric*;
Single_quoted : '\'' Sq_char+ '\'';
Distinct_object : '"' Do_char+ '"';
WS : [ \r\t\n]+ -> skip ;
Line_comment : '%' ~[\r\n]* -> skip;
Block_comment : '/*' .*? '*/' -> skip;
//%----Top of Page---------------------------------------------------------------
//%----Rules from here on down are for defining tokens (terminal symbols) of the
//%----grammar, assuming they will be recognized by a lexical scanner.
//%----A ::- rule defines a token, a ::: rule defines a macro that is not a
//%----token. Usual regexp notation is used. Single characters are always placed
//%----in []s to disable any special meanings (for uniformity this is done to
//%----all characters, not only those with special meanings).
//
//%----These are tokens that appear in the syntax rules above. No rules
//%----defined here because they appear explicitly in the syntax rules,
//%----except that <vline>, <star>, <plus> denote "|", "*", "+", respectively.
//%----Keywords: fof cnf thf tff include
//%----Punctuation: ( ) , . [ ] :
//%----Operators: ! ? ~ & | <=> => <= <~> ~| ~& * +
//%----Predicates: = != $true $false
//
//%----For lex/yacc there cannot be spaces on either side of the | here
//<comment> ::- <comment_line>|<comment_block>
//<comment_line> ::- [%]<printable_char>*
//<comment_block> ::: [/][*]<not_star_slash>[*][*]*[/]
//<not_star_slash> ::: ([^*]*[*][*]*[^/*])*[^*]*
//%----Defined comments are a convention used for annotations that are used as
//%----additional input for systems. They look like comments, but start with %$
//%----or /*$. A wily user of the syntax can notice the $ and extract information
//%----from the "comment" and pass that on as input to the system. They are
//%----analogous to pragmas in programming languages. To extract these separately
//%----from regular comments, the rules are:
//%---- <defined_comment> ::- <def_comment_line>|<def_comment_block>
//%---- <def_comment_line> ::: [%]<dollar><printable_char>*
//%---- <def_comment_block> ::: [/][*]<dollar><not_star_slash>[*][*]*[/]
//%----A string that matches both <defined_comment> and <comment> should be
//%----recognized as <defined_comment>, so put these before <comment>.
//%----Defined comments that are in use include:
//%---- TO BE ANNOUNCED
//%----System comments are a convention used for annotations that may used as
//%----additional input to a specific system. They look like comments, but start
//%----with %$$ or /*$$. A wily user of the syntax can notice the $$ and extract
//%----information from the "comment" and pass that on as input to the system.
//%----The specific system for which the information is intended should be
//%----identified after the $$, e.g., /*$$Otter 3.3: Demodulator */
//%----To extract these separately from regular comments, the rules are:
//%---- <system_comment> ::- <sys_comment_line>|<sys_comment_block>
//%---- <sys_comment_line> ::: [%]<dollar><dollar><printable_char>*
//%---- <sys_comment_block> ::: [/][*]<dollar><dollar><not_star_slash>[*][*]*[/]
//%----A string that matches both <system_comment> and <defined_comment> should
//%----be recognized as <system_comment>, so put these before <defined_comment>.
//
//<single_quoted> ::- <single_quote><sq_char><sq_char>*<single_quote>
//%----<single_quoted>s contain visible characters. \ is the escape character for
//%----' and \, i.e., \' is not the end of the <single_quoted>.
//%----The token does not include the outer quotes, e.g., 'cat' and cat are the
//%----same. See <atomic_word> for information about stripping the quotes.
//
//<distinct_object> ::- <double_quote><do_char>*<double_quote>
//%---Space and visible characters upto ~, except " and \
//%----<distinct_object>s contain visible characters. \ is the escape character
//%----for " and \, i.e., \" is not the end of the <distinct_object>.
//%----<distinct_object>s are different from (but may be equal to) other tokens,
//%----e.g., "cat" is different from 'cat' and cat. Distinct objects are always
//%----interpreted as themselves, so if they are different they are unequal,
//%----e.g., "Apple" != "Microsoft" is implicit.
//
//<dollar_word> ::- <dollar><lower_word>
//<dollar_dollar_word> ::- <dollar><dollar><lower_word>
//<upper_word> ::- <upper_alpha><alpha_numeric>*
//<lower_word> ::- <lower_alpha><alpha_numeric>*
//
//%----Tokens used in syntax, and cannot be character classes
//<vline> ::- [|]
//<star> ::- [*]
//<plus> ::- [+]
//<arrow> ::- [>]
//<less_sign> ::- [<]
//
//%----Numbers. Signs are made part of the same token here.
//<real> ::- (<signed_real>|<unsigned_real>)
//<signed_real> ::- <sign><unsigned_real>
//<unsigned_real> ::- (<decimal_fraction>|<decimal_exponent>)
//<rational> ::- (<signed_rational>|<unsigned_rational>)
//<signed_rational> ::- <sign><unsigned_rational>
//<unsigned_rational> ::- <decimal><slash><positive_decimal>
//<integer> ::- (<signed_integer>|<unsigned_integer>)
//<signed_integer> ::- <sign><unsigned_integer>
//<unsigned_integer> ::- <decimal>
//<decimal> ::- (<zero_numeric>|<positive_decimal>)
//<positive_decimal> ::- <non_zero_numeric><numeric>*
//<decimal_exponent> ::- (<decimal>|<decimal_fraction>)<exponent><exp_integer>
//<decimal_fraction> ::- <decimal><dot_decimal>
//<dot_decimal> ::- <dot><numeric><numeric>*
//<exp_integer> ::- (<signed_exp_integer>|<unsigned_exp_integer>)
//<signed_exp_integer> ::- <sign><unsigned_exp_integer>
//<unsigned_exp_integer> ::- <numeric><numeric>*
//
//%----Character classes
//<percentage_sign> ::: [%]
//<double_quote> ::: ["]
//<do_char> ::: ([\40-\41\43-\133\135-\176]|[\\]["\\])
//<single_quote> ::: [']
//%---Space and visible characters upto ~, except ' and \
//<sq_char> ::: ([\40-\46\50-\133\135-\176]|[\\]['\\])
//<sign> ::: [+-]
//<dot> ::: [.]
//<exponent> ::: [Ee]
//<slash> ::: [/]
//<zero_numeric> ::: [0]
//<non_zero_numeric> ::: [1-9]
//<numeric> ::: [0-9]
//<lower_alpha> ::: [a-z]
//<upper_alpha> ::: [A-Z]
//<alpha_numeric> ::: (<lower_alpha>|<upper_alpha>|<numeric>|[_])
//<dollar> ::: [$]
//<printable_char> ::: .
//%----<printable_char> is any printable ASCII character, codes 32 (space) to 126
//%----(tilde). <printable_char> does not include tabs, newlines, bells, etc. The
//%----use of . does not not exclude tab, so this is a bit loose.
//<viewable_char> ::: [.\n]
//%----Top of Page---------------------------------------------------------------
// #INFO HERE COMES THE GRAMMAR
//%----v7.0.0.0 (TPTP version.internal development number)
//%------------------------------------------------------------------------------
//%----README ... this header provides important meta- and usage information
//%----
//%----Intended uses of the various parts of the TPTP syntax are explained
//%----in the TPTP technical manual, linked from www.tptp.org.
//%----
//%----Four kinds of separators are used, to indicate different types of rules:
//%---- ::= is used for regular grammar rules, for syntactic parsing.
//%---- :== is used for semantic grammar rules. These define specific values
//%---- that make semantic sense when more general syntactic rules apply.
//%---- ::- is used for rules that produce tokens.
//%---- ::: is used for rules that define character classes used in the
//%---- construction of tokens.
//%----
//%----White space may occur between any two tokens. White space is not specified
//%----in the grammar, but there are some restrictions to ensure that the grammar
//%----is compatible with standard Prolog: a <TPTP_file> should be readable with
//%----read/1.
//%----
//%----The syntax of comments is defined by the <comment> rule. Comments may
//%----occur between any two tokens, but do not act as white space. Comments
//%----will normally be discarded at the lexical level, but may be processed
//%----by systems that understand them (e.g., if the system comment convention
//%----is followed).
//%----
//%----Multiple languages are defined. Depending on your need, you can implement
//%----just the one(s) you need. The common rules for atoms, terms, etc, come
//%----after the definitions of the languages, and mostly all needed for all the
//%----languages.
//%----Top of Page---------------------------------------------------------------
//%----Files. Empty file is OK.
//<TPTP_file> ::= <TPTP_input>*
//<TPTP_input> ::= <annotated_formula> | <include>
tptp_file : tptp_input* EOF;
tptp_input : annotated_formula | include;
//%----Formula records
//<annotated_formula> ::= <thf_annotated> | <tfx_annotated> | <tff_annotated> |
// <tcf_annotated> | <fof_annotated> | <cnf_annotated> |
// <tpi_annotated>
//%----Future languages may include ... english | efof | tfof | mathml | ...
//<tpi_annotated> ::= tpi(<name>,<formula_role>,<tpi_formula><annotations>).
//<tpi_formula> ::= <fof_formula>
//<thf_annotated> ::= thf(<name>,<formula_role>,<thf_formula>
// <annotations>).
//<tfx_annotated> ::= tfx(<name>,<formula_role>,<tfx_formula>
// <annotations>).
//<tff_annotated> ::= tff(<name>,<formula_role>,<tff_formula>
// <annotations>).
//<tcf_annotated> ::= tcf(<name>,<formula_role>,<tcf_formula>
// <annotations>).
//<fof_annotated> ::= fof(<name>,<formula_role>,<fof_formula>
// <annotations>).
//<cnf_annotated> ::= cnf(<name>,<formula_role>,<cnf_formula>
// <annotations>).
//<annotations> ::= ,<source><optional_info> | <null>
annotated_formula : thf_annotated | tfx_annotated | tff_annotated
| tcf_annotated | fof_annotated | cnf_annotated
| tpi_annotated;
tpi_annotated : 'tpi(' name ',' formula_role ',' tpi_formula annotations? ').';
tpi_formula : fof_formula;
thf_annotated : 'thf(' name ',' formula_role ',' thf_formula annotations? ').';
tfx_annotated : 'tfx(' name ',' formula_role ',' tfx_formula annotations? ').';
tff_annotated : 'tff(' name ',' formula_role ',' tff_formula annotations? ').';
tcf_annotated : 'tcf(' name ',' formula_role ',' tcf_formula annotations? ').';
fof_annotated : 'fof(' name ',' formula_role ',' fof_formula annotations? ').';
cnf_annotated : 'cnf(' name ',' formula_role ',' cnf_formula annotations? ').';
annotations : ',' source optional_info?;
//%----In derivations the annotated formulae names must be unique, so that
//%----parent references (see <inference_record>) are unambiguous.
//%----Types for problems.
//%----Note: The previous <source_type> from ...
//%---- <formula_role> ::= <user_role>-<source>
//%----... is now gone. Parsers may choose to be tolerant of it for backwards
//%----compatibility.
//<formula_role> ::= <lower_word>
//<formula_role> :== axiom | hypothesis | definition | assumption |
// lemma | theorem | corollary | conjecture |
// negated_conjecture | plain | type |
// fi_domain | fi_functors | fi_predicates | unknown
formula_role : Lower_word; // #RES no restrictions
//%----"axiom"s are accepted, without proof. There is no guarantee that the
//%----axioms of a problem are consistent.
//%----"hypothesis"s are assumed to be true for a particular problem, and are
//%----used like "axiom"s.
//%----"definition"s are intended to define symbols. They are either universally
//%----quantified equations, or universally quantified equivalences with an
//%----atomic lefthand side. They can be treated like "axiom"s.
//%----"assumption"s can be used like axioms, but must be discharged before a
//%----derivation is complete.
//%----"lemma"s and "theorem"s have been proven from the "axiom"s. They can be
//%----used like "axiom"s in problems, and a problem containing a non-redundant
//%----"lemma" or theorem" is ill-formed. They can also appear in derivations.
//%----"theorem"s are more important than "lemma"s from the user perspective.
//%----"conjecture"s are to be proven from the "axiom"(-like) formulae. A problem
//%----is solved only when all "conjecture"s are proven.
//%----"negated_conjecture"s are formed from negation of a "conjecture" (usually
//%----in a FOF to CNF conversion).
//%----"plain"s have no specified user semantics.
//%----"fi_domain", "fi_functors", and "fi_predicates" are used to record the
//%----domain, interpretation of functors, and interpretation of predicates, for
//%----a finite interpretation.
//%----"type" defines the type globally for one symbol; treat as $true.
//%----"unknown"s have unknown role, and this is an error situation.
//%----Top of Page---------------------------------------------------------------
//%----THF formulae.
//<thf_formula> ::= <thf_logic_formula> | <thf_sequent>
//<thf_logic_formula> ::= <thf_binary_formula> | <thf_unitary_formula> |
// <thf_type_formula> | <thf_subtype>
//<thf_binary_formula> ::= <thf_binary_pair> | <thf_binary_tuple> |
// <thf_binary_type>
thf_formula : thf_logic_formula | thf_sequent;
thf_logic_formula : thf_binary_formula | thf_unitary_formula
| thf_type_formula | thf_subtype;
thf_binary_formula : thf_binary_pair | thf_binary_tuple
| thf_binary_type;
//%----Only some binary connectives can be written without ()s.
//%----There's no precedence among binary connectives
//<thf_binary_pair> ::= <thf_unitary_formula> <thf_pair_connective>
// <thf_unitary_formula>
//<thf_binary_tuple> ::= <thf_or_formula> | <thf_and_formula> |
// <thf_apply_formula>
//<thf_or_formula> ::= <thf_unitary_formula> <vline> <thf_unitary_formula> |
// <thf_or_formula> <vline> <thf_unitary_formula>
//<thf_and_formula> ::= <thf_unitary_formula> & <thf_unitary_formula> |
// <thf_and_formula> & <thf_unitary_formula>
//%----@ (denoting apply) is left-associative and lambda is right-associative.
//%----^ [X] : ^ [Y] : f @ g (where f is a <thf_apply_formula> and g is a
//%----<thf_unitary_formula>) should be parsed as: (^ [X] : (^ [Y] : f)) @ g.
//%----That is, g is not in the scope of either lambda.
//<thf_apply_formula> ::= <thf_unitary_formula> @ <thf_unitary_formula> |
// <thf_apply_formula> @ <thf_unitary_formula>
thf_binary_pair : thf_unitary_formula thf_pair_connective thf_unitary_formula;
thf_binary_tuple : thf_or_formula | thf_and_formula
| thf_apply_formula;
thf_or_formula : thf_unitary_formula Or thf_unitary_formula
| thf_or_formula Or thf_unitary_formula;
thf_and_formula : thf_unitary_formula And thf_unitary_formula
| thf_and_formula And thf_unitary_formula;
thf_apply_formula : thf_unitary_formula App thf_unitary_formula
| thf_apply_formula App thf_unitary_formula;
//%----<thf_unitary_formula> are in ()s or do not have a <binary_connective> at
//%----the top level. Essentially, any lambda expression that "has enough ()s" to
//%----be used inside a larger lambda expression. However, lambda notation might
//%----not be used.
//<thf_unitary_formula> ::= <thf_quantified_formula> | <thf_unary_formula> |
// <thf_atom> | <thf_conditional> | <thf_let> |
// <thf_tuple> | (<thf_logic_formula>)
thf_unitary_formula : thf_quantified_formula | thf_unary_formula
| thf_atom | thf_conditional | thf_let
| thf_tuple | '(' thf_logic_formula ')';
//%----All variables must be quantified
//<thf_quantified_formula> ::= <thf_quantification> <thf_unitary_formula>
//<thf_quantification> ::= <thf_quantifier> [<thf_variable_list>] :
//<thf_variable_list> ::= <thf_variable> | <thf_variable>,<thf_variable_list>
//<thf_variable> ::= <thf_typed_variable> | <variable>
//<thf_typed_variable> ::= <variable> : <thf_top_level_type>
thf_quantified_formula : thf_quantification thf_unitary_formula;
thf_quantification : thf_quantifier '[' thf_variable_list ']' ':';
thf_variable_list : thf_variable (',' thf_variable)*; // #INFO thf_variable_list flattened
//thf_variable_list : thf_variable | thf_variable ',' thf_variable_list; // #ALT flattened to thf_variable_list
thf_variable : thf_typed_variable | variable;
thf_typed_variable : variable ':' thf_top_level_type;
//thf_variable : variable (':' thf_top_level_type)?; // #ALT to thf_variable (more condensed)
//%----Unary connectives bind more tightly than binary. The negated formula
//%----must be ()ed because a ~ is also a term.
//<thf_unary_formula> ::= <thf_unary_connective> (<thf_logic_formula>)
//<thf_atom> ::= <thf_function> | <variable> | <defined_term> |
// <thf_conn_term>
thf_unary_formula : thf_unary_connective '(' thf_logic_formula ')';
thf_atom : thf_function | variable | defined_term
| thf_conn_term;
//%----Defined terms have TPTP specific interpretations. Note that <thf_atom>
//%----allows <defined_type>s as terms, which will fail type checking. The
//%----user must take care with this liberal syntax!
//<thf_function> ::= <atom> | <functor>(<thf_arguments>) |
// <defined_functor>(<thf_arguments>) |
// <system_functor>(<thf_arguments>)
thf_function : atom | functor '(' thf_arguments ')'
| defined_functor '(' thf_arguments ')'
| system_functor '(' thf_arguments ')';
// #ALT to thf_function
// Splitted rules of <thf_function> to avoid using <atom> here:
// We use conditional arguments, i.e.
// the atoms are included (= thf_arguments is empty).
//thf_function: thf_plain_term | thf_defined_term | thf_system_term;
//thf_plain_term : functor ('(' thf_arguments ')')?;
//thf_defined_term : defined_functor ('(' thf_arguments ')')?;
//thf_system_term : system_functor ('(' thf_arguments ')')?;
//%----| <defined_type> | <defined_prop>, but they are captured by <atom> as
//%----<defined_constant> as <atomic_defined_word>.
//<thf_conn_term> ::= <thf_pair_connective> | <assoc_connective> |
// <thf_unary_connective>
thf_conn_term : thf_pair_connective | assoc_connective
| thf_unary_connective;
//%----Note that syntactically this allows (p @ =), but for = the first
//%----argument must be known to infer the type of =, so that's not
//%----allowed, i.e., only (= @ p).
//<thf_conditional> ::= $ite(<thf_logic_formula>,<thf_logic_formula>,
// <thf_logic_formula>)
thf_conditional : '$ite(' thf_logic_formula ',' thf_logic_formula ',' thf_logic_formula ')';
//%----<thf_let> is about to be changed. Don't trust anything here.
//%----The LHS of a term or formula binding must be a non-variable term that
//%----is flat with pairwise distinct variable arguments, and the variables in
//%----the LHS must be exactly those bound in the universally quantified variable
//%----list, in the same order. Let definitions are not recursive: a non-variable
//%----symbol introduced in the LHS of a let definition cannot occur in the RHS.
//%----If a symbol with the same signature as the one in the LHS of the binding
//%----is declared above the let expression (at the top level or in an
//%----encompassing let) then it can be used in the RHS of the binding, but it is
//%----not accessible in the term or formula of the let expression. Let
//%----expressions can be eliminated by a simple definition expansion.
//<thf_let> ::= $let(<thf_unitary_formula>,<thf_formula>)
//<thf_let> :== $let(<thf_let_defns>,<thf_formula>)
//<thf_let_defns> :== <thf_let_defn> | [<thf_let_defn_list>]
//<thf_let_defn_list> :== <thf_let_defn> | <thf_let_defn>,<thf_let_defn_list>
//<thf_let_defn> :== <thf_let_quantified_defn> | <thf_let_plain_defn>
//<thf_let_quantified_defn> :== <thf_quantification> (<thf_let_plain_defn>)
//<thf_let_plain_defn> :== <thf_let_defn_LHS> <assignment> <thf_formula>
//<thf_let_defn_LHS> :== <constant> | <functor>(<fof_arguments>) |
// <thf_tuple>
thf_let : '$let(' thf_unitary_formula ',' thf_formula ')';
// TODO nothing since it is about to be changed
//%----The <fof_arguments> must all be <variable>s, and the <thf_tuple> may
//%----contain only <constant>s and <functor>(<fof_arguments>)s
//
//%----Arguments recurse back up to formulae (this is the THF world here)
//<thf_arguments> ::= <thf_formula_list>
thf_arguments : thf_formula_list;
//%----A <thf_type_formula> is an assertion that the formula is in this type.
//<thf_type_formula> ::= <thf_typeable_formula> : <thf_top_level_type>
//<thf_typeable_formula> ::= <thf_atom> | (<thf_logic_formula>)
//<thf_subtype> ::= <thf_atom> <subtype_sign> <thf_atom>
thf_type_formula : thf_typeable_formula ':' thf_top_level_type;
thf_typeable_formula : thf_atom | '(' thf_logic_formula ')';
thf_subtype : thf_atom Subtype_sign thf_atom;
//%----In a formula with role 'type', <thf_type_formula> is a global declaration
//%----that <constant> is in this thf_top_level_type>, i.e., the rule is ...
//<thf_type_formula> :== <constant> : <thf_top_level_type>
// #INFO the previous thf_type_formula leads to constant on the left side of the :
//thf_type_formula : constant ':' thf_top_level_type;
//%----<thf_top_level_type> appears after ":", where a type is being specified
//%----for a term or variable. <thf_unitary_type> includes <thf_unitary_formula>,
//%----so the syntax allows just about any lambda expression with "enough"
//%----parentheses to serve as a type. The expected use of this flexibility is
//%----parametric polymorphism in types, expressed with lambda abstraction.
//%----Mapping is right-associative: o > o > o means o > (o > o).
//%----Xproduct is left-associative: o * o * o means (o * o) * o.
//%----Union is left-associative: o + o + o means (o + o) + o.
//<thf_top_level_type> ::= <thf_unitary_type> | <thf_mapping_type> |
// <thf_apply_type>
thf_top_level_type : thf_unitary_type | thf_mapping_type | thf_apply_type;
//%----Removed along with adding <thf_binary_type> to <thf_binary_formula>, for
//%----TH1 polymorphic types with binary after quantification.
//%---- | (<thf_binary_type>)
//<thf_unitary_type> ::= <thf_unitary_formula>
//<thf_apply_type> ::= <thf_apply_formula>
//<thf_binary_type> ::= <thf_mapping_type> | <thf_xprod_type> |
// <thf_union_type>
//<thf_mapping_type> ::= <thf_unitary_type> <arrow> <thf_unitary_type> |
// <thf_unitary_type> <arrow> <thf_mapping_type>
//<thf_xprod_type> ::= <thf_unitary_type> <star> <thf_unitary_type> |
// <thf_xprod_type> <star> <thf_unitary_type>
//<thf_union_type> ::= <thf_unitary_type> <plus> <thf_unitary_type> |
// <thf_union_type> <plus> <thf_unitary_type>
thf_unitary_type : thf_unitary_formula;
thf_apply_type : thf_apply_formula;
thf_binary_type : thf_mapping_type | thf_xprod_type
| thf_union_type;
thf_mapping_type : thf_unitary_type Arrow thf_unitary_type
| thf_unitary_type Arrow thf_mapping_type;
thf_xprod_type : thf_unitary_type Star thf_unitary_type
| thf_xprod_type Star thf_unitary_type;
thf_union_type : thf_unitary_type Plus thf_unitary_type
| thf_union_type Plus thf_unitary_type;
//%----Sequents using the Gentzen arrow
//<thf_sequent> ::= <thf_tuple> <gentzen_arrow> <thf_tuple> |
// (<thf_sequent>)
thf_sequent : thf_tuple Gentzen_arrow thf_tuple
| '(' thf_sequent ')';
//%----By convention, []s are used for tuple of statements, {}s for tuples of
//%----objects. The convention matches the requirements for <tff_tuple_formula>s
//%----and <tff_tuple_term>s. Mixed THF tuples should use []s.
//<thf_tuple> ::= [] | [<thf_formula_list>] |
// {} | {<thf_formula_list>}
//<thf_formula_list> ::= <thf_logic_formula> |
// <thf_logic_formula>,<thf_formula_list>
thf_tuple : '[]' | '[' thf_formula_list ']'
| '{}' | '{' thf_formula_list '}';
thf_formula_list : thf_logic_formula (',' thf_logic_formula)*;
//%----New material for modal logic semantics, not integrated yet
//<logic_defn_rule> :== <logic_defn_LHS> <assignment> <logic_defn_RHS>
//<logic_defn_LHS> :== <logic_defn_value> | <thf_top_level_type> | <name>
//<logic_defn_LHS> :== $constants | $quantification | $consequence |
// $modalities
//logic_defn_rule : logic_defn_lhs Assignment logic_defn_rhs;
//logic_defn_lhs : logic_defn_value // TODO dunno why this is there
// | thf_function // for constant selection
// | thf_top_level_type // for domain selection
// | name // for axioms selection
// | Dollar_word; // #RES no restrictions
//| '$modal' // enables modal logical options
//| '$constants' // modal logic: alter constants
//| '$quantification' // modal logic: alter quantification
//| '$consequence' // modal logic: alter consequence
//| '$modalities'; // modal logic: alter modality operators
//%----The $constants, $quantification, and $consequence apply to all of the
//%----$modalities. Each of these may be specified only once, but not necessarily
//%----all in a single annotated formula.
//<logic_defn_RHS> :== <logic_defn_value> | <thf_unitary_formula>
//<logic_defn_value> :== <defined_constant>
//<logic_defn_value> :== $rigid | $flexible |
// $constant | $varying | $cumulative | $decreasing |
// $local | $global |
// $modal_system_K | $modal_system_T | $modal_system_D |
// $modal_system_S4 | $modal_system_S5 |
// $modal_axiom_K | $modal_axiom_T | $modal_axiom_B |
// $modal_axiom_D | $modal_axiom_4 | $modal_axiom_5
//logic_defn_rhs : logic_defn_value
// | thf_unitary_formula; // TODO dunno why this is there
//logic_defn_value : Dollar_word; // #RES no restrictions
// '$rigid' // modal logic: consequence option
// | '$flexible' // modal logic: consequence option
// | '$constant' // modal logic: quantification option
// | '$varying' // modal logic: quantification option
// | '$cumulative' // modal logic: quantification option
// | '$decreasing' // modal logic: quantification option
// | '$local' // modal logic: consequence option
// | '$global' // modal logic: consequence option
// | '$modal_system_K' // modal logic: Axiom: K
// | '$modal_system_T' // modal logic: Axiom: K + T
// | '$modal_system_D' // modal logic: Axiom: K + D
// | '$modal_system_S4' // modal logic: Axiom K + T + 4
// | '$modal_system_S5' // modal logic: Axiom K + T + 5
// | '$modal_axiom_K' // modal logic: box(s -> t) -> (box s -> box t)
// | '$modal_axiom_T' // modal logic: box s -> s
// | '$modal_axiom_B' // modal logic: s -> box dia s
// | '$modal_axiom_D' // modal logic: box s -> dia s
// | '$modal_axiom_4' // modal logic: box s -> box box s
// | '$modal_axiom_5' // modal logic: dia s -> box dia s
// | '$modal_axiom_CD' // modal logic: dia s -> box s
// | '$modal_axiom_BOXM' // modal logic: box (box s -> s)
// | '$modal_axiom_C4' // modal logic: box box s -> box s
// | '$modal_axiom_C'; // modal logic: dia box s -> box dia s
//%----Top of Page---------------------------------------------------------------
//%----TFX formulae
//<tfx_formula> ::= <tfx_logic_formula> | <thf_sequent>
//<tfx_logic_formula> ::= <thf_logic_formula>
//% <tfx_logic_formula> ::= <thf_binary_formula> | <thf_unitary_formula> |
//% <tff_typed_atom> | <tff_subtype>
tfx_formula : tfx_logic_formula | thf_sequent;
tfx_logic_formula : thf_logic_formula;
//%----Top of Page---------------------------------------------------------------
//%----TFF formulae.
//<tff_formula> ::= <tff_logic_formula> | <tff_typed_atom> |
// <tff_sequent>
//<tff_logic_formula> ::= <tff_binary_formula> | <tff_unitary_formula> |
// <tff_subtype>
//<tff_binary_formula> ::= <tff_binary_nonassoc> | <tff_binary_assoc>
//<tff_binary_nonassoc> ::= <tff_unitary_formula> <binary_connective>
// <tff_unitary_formula>
//<tff_binary_assoc> ::= <tff_or_formula> | <tff_and_formula>
//<tff_or_formula> ::= <tff_unitary_formula> <vline> <tff_unitary_formula> |
// <tff_or_formula> <vline> <tff_unitary_formula>
//<tff_and_formula> ::= <tff_unitary_formula> & <tff_unitary_formula> |
// <tff_and_formula> & <tff_unitary_formula>
//<tff_unitary_formula> ::= <tff_quantified_formula> | <tff_unary_formula> |
// <tff_atomic_formula> | <tff_conditional> |
// <tff_let> | (<tff_logic_formula>)
tff_formula : tff_logic_formula | tff_typed_atom
| tff_sequent;
tff_logic_formula : tff_binary_formula | tff_unitary_formula
| tff_subtype;
tff_binary_formula : tff_binary_nonassoc | tff_binary_assoc;
tff_binary_nonassoc : tff_unitary_formula binary_connective tff_unitary_formula;
tff_binary_assoc : tff_or_formula | tff_and_formula;
tff_or_formula : tff_unitary_formula Or tff_unitary_formula
| tff_or_formula Or tff_unitary_formula;
tff_and_formula : tff_unitary_formula And tff_unitary_formula
| tff_and_formula And tff_unitary_formula;
tff_unitary_formula : tff_quantified_formula | tff_unary_formula
| tff_atomic_formula | tff_conditional
| tff_let | '(' tff_logic_formula ')';
//%----All variables must be quantified
//<tff_quantified_formula> ::= <fof_quantifier> [<tff_variable_list>] :
// <tff_unitary_formula>
//<tff_variable_list> ::= <tff_variable> | <tff_variable>,<tff_variable_list>
//<tff_variable> ::= <tff_typed_variable> | <variable>
//<tff_typed_variable> ::= <variable> : <tff_atomic_type>
//<tff_unary_formula> ::= <unary_connective> <tff_unitary_formula> |
// <fof_infix_unary>
//<tff_atomic_formula> ::= <fof_atomic_formula>
tff_quantified_formula : fof_quantifier '[' tff_variable_list ']' ':' tff_unitary_formula;
tff_variable_list : tff_variable (',' tff_variable)*; // #INFO tff_variable_list flattened
//tff_variable_list : tff_variable | tff_variable ',' tff_variable_list; // # ALT to tff_variable_list
tff_variable : tff_typed_variable | variable;
// tff_variable : variable (':' tff_atomic_type)?; // #ALT to tff_variable (more condensed)
tff_typed_variable : variable ':' tff_atomic_type;
tff_unary_formula : unary_connective tff_unitary_formula
| fof_infix_unary;
tff_atomic_formula : fof_atomic_formula;
//<tff_conditional> ::= $ite_f(<tff_logic_formula>,<tff_logic_formula>,
// <tff_logic_formula>)
//<tff_let> ::= $let_tf(<tff_let_term_defns>,<tff_formula>) |
// $let_ff(<tff_let_formula_defns>,<tff_formula>)
//%----See the commentary for <thf_let>.
//<tff_let_term_defns> ::= <tff_let_term_defn> | [<tff_let_term_list>]
//<tff_let_term_list> ::= <tff_let_term_defn> |
// <tff_let_term_defn>,<tff_let_term_list>
//<tff_let_term_defn> ::= ! [<tff_variable_list>] : <tff_let_term_defn> |
// <tff_let_term_binding>
//<tff_let_term_binding> ::= <fof_plain_term> = <fof_term> |
// (<tff_let_term_binding>)
//<tff_let_formula_defns> ::= <tff_let_formula_defn> | [<tff_let_formula_list>]
//<tff_let_formula_list> ::= <tff_let_formula_defn> |
// <tff_let_formula_defn>,<tff_let_formula_list>
//<tff_let_formula_defn> ::= ! [<tff_variable_list>] : <tff_let_formula_defn> |
// <tff_let_formula_binding>
//<tff_let_formula_binding> ::= <fof_plain_atomic_formula> <=>
// <tff_unitary_formula> | (<tff_let_formula_binding>)
tff_conditional : '$ite_f(' tff_logic_formula ',' tff_logic_formula ',' tff_logic_formula ')';
tff_let : '$let_tf(' tff_let_term_defns ',' tff_formula ')'
| '$let_ff(' tff_let_formula_defns ',' tff_formula ')';
tff_let_term_defns : tff_let_term_defn | '[' tff_let_term_list ']';
tff_let_term_list : tff_let_term_defn (',' tff_let_term_defn)*;
tff_let_term_defn : Forall '[' tff_variable_list ']' ':' tff_let_term_defn
| tff_let_term_binding;
tff_let_term_binding : fof_plain_term Infix_equality fof_term
| '(' tff_let_term_binding ')';
tff_let_formula_defns : tff_let_formula_defn | '[' tff_let_formula_list ']';
tff_let_formula_list : tff_let_formula_defn (',' tff_let_formula_defn)*;
tff_let_formula_defn : Forall '[' tff_variable_list ']' ':' tff_let_formula_defn
| tff_let_formula_binding;
tff_let_formula_binding : fof_plain_atomic_formula Iff tff_unitary_formula
| '(' tff_let_formula_binding ')';
//<tff_sequent> ::= <tff_formula_tuple> <gentzen_arrow>
// <tff_formula_tuple> | (<tff_sequent>)
//<tff_formula_tuple> ::= [] | [<tff_formula_tuple_list>]
//<tff_formula_tuple_list> ::= <tff_logic_formula> |
// <tff_logic_formula>,<tff_formula_tuple_list>
tff_sequent : tff_formula_tuple Gentzen_arrow tff_formula_tuple
| '(' tff_sequent ')';
tff_formula_tuple : '[]' | '[' tff_formula_tuple_list ']';
tff_formula_tuple_list : tff_logic_formula (',' tff_logic_formula)*;
//%----<tff_typed_atom> can appear only at top level
//<tff_typed_atom> ::= <untyped_atom> : <tff_top_level_type> |
// (<tff_typed_atom>)
//
//<tff_subtype> ::= <untyped_atom> <subtype_sign> <atom>
tff_typed_atom : untyped_atom ':' tff_top_level_type
| '(' tff_typed_atom ')';
tff_subtype : untyped_atom Subtype_sign atom;
//%----See <thf_top_level_type> for commentary.
//<tff_top_level_type> ::= <tff_atomic_type> | <tff_mapping_type> |
// <tf1_quantified_type> | (<tff_top_level_type>)
//<tf1_quantified_type> ::= !> [<tff_variable_list>] : <tff_monotype>
//<tff_monotype> ::= <tff_atomic_type> | (<tff_mapping_type>)
//<tff_unitary_type> ::= <tff_atomic_type> | (<tff_xprod_type>)
//<tff_atomic_type> ::= <type_constant> | <defined_type> |
// <type_functor>(<tff_type_arguments>) | <variable>
//<tff_type_arguments> ::= <tff_atomic_type> |
// <tff_atomic_type>,<tff_type_arguments>
//%----For consistency with <thf_unitary_type> (the analogue in thf),
//%----<tff_atomic_type> should also allow (<tff_atomic_type>), but that causes
//%----ambiguity.
//<tff_mapping_type> ::= <tff_unitary_type> <arrow> <tff_atomic_type>
//<tff_xprod_type> ::= <tff_unitary_type> <star> <tff_atomic_type> |
// <tff_xprod_type> <star> <tff_atomic_type>
tff_top_level_type : tff_atomic_type | tff_mapping_type
| tf1_quantified_type | '(' tff_top_level_type ')';
tf1_quantified_type : '!>' '[' tff_variable_list ']' ':' tff_monotype;
tff_monotype : tff_atomic_type | '(' tff_mapping_type ')';
tff_unitary_type : tff_atomic_type | '(' tff_xprod_type ')';
tff_atomic_type : type_constant | defined_type
| type_functor '(' tff_type_arguments ')' | variable;
// tff_atomic_type : defined_type | type_functor ('(' tff_type_arguments ')')? | variable; // #ALT to tff_atomic_type (more condensed)
tff_type_arguments : tff_atomic_type (',' tff_atomic_type)*;
tff_mapping_type : tff_unitary_type Arrow tff_atomic_type;
tff_xprod_type : tff_unitary_type Star tff_atomic_type
| tff_xprod_type Star tff_atomic_type;
//%----Top of Page---------------------------------------------------------------
//%----TCF formulae.
//<tcf_formula> ::= <tcf_logic_formula> | <tff_typed_atom>
//<tcf_logic_formula> ::= <tcf_quantified_formula> | <cnf_formula>
//<tcf_quantified_formula> ::= ! [<tff_variable_list>] : <cnf_formula>
tcf_formula : tcf_logic_formula | tff_typed_atom;
tcf_logic_formula : tcf_quantified_formula | cnf_formula;
tcf_quantified_formula : Forall '[' tff_variable_list ']' ':' cnf_formula;
//%----Top of Page---------------------------------------------------------------
//%----FOF formulae.
//<fof_formula> ::= <fof_logic_formula> | <fof_sequent>
//<fof_logic_formula> ::= <fof_binary_formula> | <fof_unitary_formula>
//%----Future answer variable ideas | <answer_formula>
//<fof_binary_formula> ::= <fof_binary_nonassoc> | <fof_binary_assoc>
//%----Only some binary connectives are associative
//%----There's no precedence among binary connectives
//<fof_binary_nonassoc> ::= <fof_unitary_formula> <binary_connective>
// <fof_unitary_formula>
//%----Associative connectives & and | are in <binary_assoc>
//<fof_binary_assoc> ::= <fof_or_formula> | <fof_and_formula>
//<fof_or_formula> ::= <fof_unitary_formula> <vline> <fof_unitary_formula> |
// <fof_or_formula> <vline> <fof_unitary_formula>
//<fof_and_formula> ::= <fof_unitary_formula> & <fof_unitary_formula> |
// <fof_and_formula> & <fof_unitary_formula>
//%----<fof_unitary_formula> are in ()s or do not have a <binary_connective> at
//%----the top level.
//<fof_unitary_formula> ::= <fof_quantified_formula> | <fof_unary_formula> |
// <fof_atomic_formula> | (<fof_logic_formula>)
//%----All variables must be quantified
//<fof_quantified_formula> ::= <fof_quantifier> [<fof_variable_list>] :
// <fof_unitary_formula>
//<fof_variable_list> ::= <variable> | <variable>,<fof_variable_list>
//<fof_unary_formula> ::= <unary_connective> <fof_unitary_formula> |
// <fof_infix_unary>
fof_formula : fof_logic_formula | fof_sequent;
fof_logic_formula : fof_binary_formula | fof_unitary_formula;
fof_binary_formula : fof_binary_nonassoc | fof_binary_assoc;
fof_binary_nonassoc : fof_unitary_formula binary_connective fof_unitary_formula;
fof_binary_assoc : fof_or_formula | fof_and_formula;
fof_or_formula : fof_unitary_formula Or fof_unitary_formula
| fof_or_formula Or fof_unitary_formula;
fof_and_formula : fof_unitary_formula And fof_unitary_formula
| fof_and_formula And fof_unitary_formula;
fof_unitary_formula : fof_quantified_formula | fof_unary_formula
| fof_atomic_formula | '(' fof_logic_formula ')';
fof_quantified_formula : fof_quantifier '[' fof_variable_list ']' ':' fof_unitary_formula;
fof_variable_list : variable (',' variable)*;
fof_unary_formula : unary_connective fof_unitary_formula | fof_infix_unary;
//%----<fof_term> != <fof_term> is equivalent to ~ <fof_term> = <fof_term>
//<fof_infix_unary> ::= <fof_term> <infix_inequality> <fof_term>
//<fof_atomic_formula> ::= <fof_plain_atomic_formula> |
// <fof_defined_atomic_formula> |
// <fof_system_atomic_formula>
//<fof_plain_atomic_formula> ::= <fof_plain_term>
//<fof_plain_atomic_formula> :== <proposition> | <predicate>(<fof_arguments>)
//<fof_defined_atomic_formula> ::= <fof_defined_plain_formula> |
// <fof_defined_infix_formula>
//<fof_defined_plain_formula> ::= <fof_defined_plain_term>
//<fof_defined_plain_formula> :== <defined_proposition> |
// <defined_predicate>(<fof_arguments>)
//<fof_defined_infix_formula> ::= <fof_term> <defined_infix_pred> <fof_term>
//%----System terms have system specific interpretations
//<fof_system_atomic_formula> ::= <fof_system_term>
//%----<fof_system_atomic_formula>s are used for evaluable predicates that are
//%----available in particular tools. The predicate names are not controlled by
//%----the TPTP syntax, so use with due care. Same for <fof_system_term>s.
fof_infix_unary : fof_term Infix_inequality fof_term;
fof_atomic_formula : fof_plain_atomic_formula
| fof_defined_atomic_formula
| fof_system_atomic_formula;
fof_plain_atomic_formula : fof_plain_term;
fof_defined_atomic_formula : fof_defined_plain_formula | fof_defined_infix_formula;
fof_defined_plain_formula : fof_defined_term;
fof_defined_infix_formula : fof_term defined_infix_pred fof_term;
fof_system_atomic_formula : fof_system_term;
//%----FOF terms.
//<fof_plain_term> ::= <constant> | <functor>(<fof_arguments>)
//%----Defined terms have TPTP specific interpretations
//<fof_defined_term> ::= <defined_term> | <fof_defined_atomic_term>
//<fof_defined_atomic_term> ::= <fof_defined_plain_term>
//%----None yet | <defined_infix_term>
//%----None yet <defined_infix_term> ::= <fof_term> <defined_infix_func> <fof_term>
//%----None yet <defined_infix_func> ::=
//<fof_defined_plain_term> ::= <defined_constant> |
// <defined_functor>(<fof_arguments>)
//%----System terms have system specific interpretations
//<fof_system_term> ::= <system_constant> | <system_functor>(<fof_arguments>)
fof_plain_term : constant
| functor '(' fof_arguments ')';
fof_defined_term : defined_term | fof_defined_atomic_term;
fof_defined_atomic_term : fof_defined_plain_term;
fof_defined_plain_term : defined_constant
| defined_functor '(' fof_arguments ')';
fof_system_term : system_constant
| system_functor '(' fof_arguments ')';
// #ALT alternatives for these terms
//fof_plain_term: functor ('(' fof_arguments ')')?; // contracted for easier handling
//fof_defined_term: defined_functor ('(' fof_arguments ')')?; // contracted for easier handling
//fof_system_term: system_functor ('(' fof_arguments ')')?; // contracted for easier handling
//%----Arguments recurse back to terms (this is the FOF world here)
//<fof_arguments> ::= <fof_term> | <fof_term>,<fof_arguments>
//%----These are terms used as arguments. Not the entry point for terms because
//%----<fof_plain_term> is also used as <fof_plain_atomic_formula>. The <tff_
//%----options are for only TFF, but are here because <fof_plain_atomic_formula>
//%----is used in <fof_atomic_formula>, which is also used as
//%----<tff_atomic_formula>.
//<fof_term> ::= <fof_function_term> | <variable> |
// <tff_conditional_term> | <tff_let_term> |
// <tff_tuple_term>
//<fof_function_term> ::= <fof_plain_term> | <fof_defined_term> |
// <fof_system_term>
fof_arguments : fof_term (',' fof_term)*;
fof_term : fof_function_term | variable
| tff_conditional_term | tff_let_term
| tff_tuple_term;
fof_function_term : fof_plain_term | fof_defined_term
| fof_system_term;
//%----Conditional terms should be used by only TFF.
//<tff_conditional_term> ::= $ite_t(<tff_logic_formula>,<fof_term>,<fof_term>)
//%----Let terms should be used by only TFF. $let_ft is for use when there is
//%----a $ite_t in the <fof_term>. See the commentary for $let_tf and $let_ff.
//<tff_let_term> ::= $let_ft(<tff_let_formula_defns>,<fof_term>) |
// $let_tt(<tff_let_term_defns>,<fof_term>)
//%----<tff_tuple_term> uses {}s to disambiguate from tuples of formulae in []s.
//<tff_tuple_term> ::= {} | {<fof_arguments>}
tff_conditional_term : '$ite_t(' tff_logic_formula ',' fof_term ',' fof_term ')';
tff_let_term : '$let_ft(' tff_let_formula_defns ',' fof_term ')'
| '$let_tt(' tff_let_term_defns ',' fof_term ')';
tff_tuple_term : '{}' | '{' fof_arguments '}';
//%----Top of Page---------------------------------------------------------------
//%----This section is the FOFX syntax. Not yet in use.
//% <fof_let> ::= := [<fof_let_list>] : <fof_unitary_formula>
//% <fof_let_list> ::= <fof_defined_var> |
//% <fof_defined_var>,<fof_let_list>
//% <fof_defined_var> ::= <variable> := <fof_logic_formula> |
//% <variable> :- <fof_term> | (<fof_defined_var>)
//%
//% <fof_conditional> ::= $ite_f(<fof_logic_formula>,<fof_logic_formula>,
//% <fof_logic_formula>)
//%
//% <fof_conditional_term> ::= $ite_t(<fof_logic_formula>,<fof_term>,<fof_term>)
// #INFO not yet in use therefore not implemented
//<fof_sequent> ::= <fof_formula_tuple> <gentzen_arrow>
// <fof_formula_tuple> | (<fof_sequent>)
//
//<fof_formula_tuple> ::= [] | [<fof_formula_tuple_list>]
//<fof_formula_tuple_list> ::= <fof_logic_formula> |
// <fof_logic_formula>,<fof_formula_tuple_list>
fof_sequent : fof_formula_tuple Gentzen_arrow fof_formula_tuple
| '(' fof_sequent ')';
fof_formula_tuple : '[]' | '[' fof_formula_tuple_list ']';
fof_formula_tuple_list : fof_logic_formula (',' fof_logic_formula)*;
//%----Top of Page---------------------------------------------------------------
//%----CNF formulae (variables implicitly universally quantified)
//<cnf_formula> ::= <disjunction> | (<disjunction>)
//<disjunction> ::= <literal> | <disjunction> <vline> <literal>
//<literal> ::= <fof_atomic_formula> | ~ <fof_atomic_formula> |
// <fof_infix_unary>
cnf_formula : cnf_disjunction | '(' cnf_disjunction ')';
cnf_disjunction : cnf_literal | cnf_disjunction Or cnf_literal;
cnf_literal : fof_atomic_formula | Not fof_atomic_formula
| fof_infix_unary;
//%----Top of Page---------------------------------------------------------------
//%----Connectives - THF
//<thf_quantifier> ::= <fof_quantifier> | <th0_quantifier> |
// <th1_quantifier>
//%----TH0 quantifiers are also available in TH1
//<th1_quantifier> ::= !> | ?*
//<th0_quantifier> ::= ^ | @+ | @-
//<thf_pair_connective> ::= <infix_equality> | <infix_inequality> |
// <binary_connective> | <assignment>
//<thf_unary_connective> ::= <unary_connective> | <th1_unary_connective>
//<th1_unary_connective> ::= !! | ?? | @@+ | @@- | @=
thf_quantifier : fof_quantifier | th0_quantifier
| th1_quantifier;
th0_quantifier : Lambda | Choice | Description;
th1_quantifier : TyForall | TyExists;
thf_pair_connective : Infix_equality | Infix_inequality
| binary_connective | Assignment ;
thf_unary_connective : unary_connective | th1_unary_connective;
th1_unary_connective : ForallComb | ExistsComb | ChoiceComb | DescriptionComb | EqComb;
//%----Connectives - THF and TFF
//<subtype_sign> ::= <<
// #INFO See Lexer rules
//%----Connectives - TFF
//% <tff_pair_connective> ::= <binary_connective> | <assignment>
tff_pair_connective : binary_connective | Assignment;
//%----Connectives - FOF
//<fof_quantifier> ::= ! | ?
//<binary_connective> ::= <=> | => | <= | <~> | ~<vline> | ~&
//<assoc_connective> ::= <vline> | &
//<unary_connective> ::= ~
fof_quantifier: Forall | Exists;
binary_connective: Iff | Impl | If | Niff | Nor | Nand;
assoc_connective : Or | And;
unary_connective : Not;
//%----The seqent arrow
//<gentzen_arrow> ::= -->
//<assignment> ::= :=
// #INFO See Lexer rules for definitions
//%----Types for THF and TFF
//<type_constant> ::= <type_functor>
//<type_functor> ::= <atomic_word>
//<defined_type> ::= <atomic_defined_word>
//<defined_type> :== $oType | $o | $iType | $i | $tType |
// $real | $rat | $int
//%----$oType/$o is the Boolean type, i.e., the type of $true and $false.
//%----$iType/$i is non-empty type of individuals, which may be finite or
//%----infinite. $tType is the type of all types. $real is the type of <real>s.
//%----$rat is the type of <rational>s. $int is the type of <signed_integer>s
//%----and <unsigned_integer>s.
//<system_type> :== <atomic_system_word>
type_constant : type_functor;
type_functor : atomic_word;
// #PREDEF
defined_type : Dollar_word; // #RES no restrictions //Defined_type;
//Defined_type : '$oType' | '$o' | '$iType' | '$i' | '$tType' |
// '$real' | '$rat' | '$int';
// #UNDEF
//defined_type : atomic_defined_word;
system_type : atomic_system_word;
//%----For all language types
//<atom> ::= <untyped_atom> | <defined_constant>
//<untyped_atom> ::= <constant> | <system_constant>
atom : untyped_atom | defined_constant;
untyped_atom : constant | system_constant;
//<defined_proposition> :== <atomic_defined_word>
//<defined_proposition> :== $true | $false
//<defined_predicate> :== <atomic_defined_word>
//<defined_predicate> :== $distinct |
// $less | $lesseq | $greater | $greatereq |
// $is_int | $is_rat |
// $box_P | $box_i | $box_int | $box |
// $dia_P | $dia_i | $dia_int | $dia
// #PREDEF
defined_proposition : Dollar_word; // #RES // Defined_proposition;
// Defined_proposition : '$true' | '$false';
defined_predicate : Dollar_word; // #RES // Defined_predicate;
//Defined_predicate : '$distinct'
// | '$less' | '$lesseq' | '$greater' | '$greatereq'
// | '$is_int' | '$is_rat'
// | '$box_P' | '$box_i' | '$box_int' | '$box'
// | '$dia_P' | '$dia_i' | '$dia_int' | '$dia';
//# UNDEF
// defined_proposition : atomic_defined_word;
// defined_predicate : atomic_defined_word;
//%----$distinct means that each of it's constant arguments are pairwise !=. It
//%----is part of the TFF syntax. It can be used only as a fact, not under any
//%----connective.
//<defined_infix_pred> ::= <infix_equality> | <assignment>
//<infix_equality> ::= =
//<infix_inequality> ::= !=
defined_infix_pred : Infix_equality | Assignment;
//# INFO See lexer rules for definitions
//<constant> ::= <functor>
//<functor> ::= <atomic_word>
constant : functor;
functor : atomic_word;