/* Part of SWI-Prolog Author: Jan Wielemaker E-mail: J.Wielemaker@vu.nl WWW: http://www.swi-prolog.org Copyright (c) 2006-2018, University of Amsterdam CWI, Amsterdam All rights reserved. Redistribution and use in source and binary forms, with or without modification, are permitted provided that the following conditions are met: 1. Redistributions of source code must retain the above copyright notice, this list of conditions and the following disclaimer. 2. Redistributions in binary form must reproduce the above copyright notice, this list of conditions and the following disclaimer in the documentation and/or other materials provided with the distribution. THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. */ :- module(pldoc_search, [ search_form//1, % +Options, // search_reply//2, % +Search, +Options, // matching_object_table//2 % +Objects, +Options, // ]). :- use_module(library(http/html_write)). :- use_module(library(http/html_head)). :- use_module(library(dcg/basics)). :- use_module(library(option)). :- use_module(library(pairs)). :- use_module(library(uri)). :- use_module(library(debug)). :- use_module(library(apply)). :- use_module(library(lists)). :- use_module(library(atom)). :- use_module(library(porter_stem)). :- use_module(doc_process). :- use_module(doc_html). :- use_module(doc_index). :- use_module(doc_util). :- use_module(doc_words). :- use_module(man_index). :- include(hooks). /** Search form and reply @tbd Advanced search field * Limit to a directory * Whole-word search */ :- predicate_options(search_form//1, 1, [ for(atom), search_in(oneof([all,noapp,app,man])), search_match(oneof([name,summary])), search_options(boolean) ]). :- predicate_options(search_reply//2, 2, [ resultFormat(oneof([summary,long])), search_in(oneof([all,noapp,app,man])), search_match(oneof([name,summary])), header(boolean), private(boolean), edit(boolean), page(positive_integer), per_page(positive_integer), pass_to(pldoc_index:doc_links//2, 2) ]). %! search_form(+Options)// % % Create a search input field. The input field points to % =|/search?for=String|= on the current server. Options: % % * title(Title) search_form(Options) --> { ( option(for(Value), Options) -> Extra = [value(Value)] ; Extra = [] ), option(search_in(In), Options, all), option(search_match(Match), Options, summary) }, html(form([ id('search-form'), action(location_by_id(pldoc_search)) ], [ div([ \search_field([ name(for), id(for) | Extra ]) ]), \search_options(In, Match, Options) ])). search_options(In, Match, Options) --> { option(search_options(false), Options) }, !, hidden(in, In), hidden(match, Match). search_options(In, Match, _Options) --> html(div(class('search-options'), [ span(class('search-in'), [ \radio(in, all, 'All', In), \radio(in, app, 'Application', In), \radio(in, man, 'Manual', In) ]), span(class('search-match'), [ \radio(match, name, 'Name', Match), \radio(match, summary, 'Summary', Match) ]), span(class('search-help'), [ a(href(location_by_id(pldoc_package)+'pldoc.html#sec:browser'), 'Help') ]) ])). %! search_field(+Options)// is det. % % Hookable predicate to display the search field. Hookability is % provided to experiment with auto-completion outside this % package. search_field(Options) --> prolog:doc_search_field(Options), !. search_field(Options) --> html([ input(Options, []), input([ id('submit-for'), type(submit), value('Search') ]) ]). radio(Radio, Field, Label, In) --> { Field == In -> Extra = [checked] ; Extra = [] }, html([ input([ type(radio), name(Radio), value(Field) | Extra ]), Label ]). hidden(Name, Value) --> html(input([type(hidden), name(Name), value(Value)])). %! search_reply(+For, +Options)// is det. % % Generate a reply searching for For. Options include % % * resultFormat(Format) % If =summary= (default), produce a summary-table. If % =long=, produce full object descriptions. % % * search_in(In) % Determine which databases to search. One of % =all=, =app=, =man= % % * private(Boolean) % If `false` (default `true`), hide private predicates % from results. % % * search_match(Match) % What part of the object to match. One of =name=, % =summary= % % * header(+Boolean) % If =false=, suppress the header. % % * per_page(+positive_integer) % Number of results per page (default 25). % % * page(+positive_integer) % Page number to show results for (default 1). :- html_meta search_header(+, html, +, ?, ?). search_reply(For, Options) --> { var(For) ; For == '' }, !, search_header('', 'Using PlDoc search', Options), html([ ul( class('search-help'), [ li([ 'If you pause typing, the search box will display ', 'an auto completion list. Selecting an object jumps ', 'immediately to the corresponding documentation.' ]), li([ 'Searching for ', i('Name/Arity'), ', ', i('Name//Arity'), ', ', i('Name'), ' or ', i('C-function()'), ' ensures that ', 'matching definitions appear first in the search ', 'results' ]), li([ 'Other searches search through the name and summary ', 'descriptions in the manual.' ]) ]) ]). search_reply(For, Options) --> { cached_search(For, PerCategory, Time, Options), PerCategory \== [], page_location(PerCategory, NPages, Offset, Limit, Options), option(resultFormat(Format), Options, summary) }, !, search_header(For, [ 'Search results for ', span(class(for), ['"', For, '"']) ], Options), { DisplayOptions = [ for(For), cputime(Time), page_count(NPages) | Options ] }, indexed_matches(Format, PerCategory, Offset, Limit, DisplayOptions), search_pagination(DisplayOptions). search_reply(For, Options) --> search_header(For, 'No matches', Options), html(div(class('search-no-matches'), 'No matches')). :- dynamic cached_search_result/4. cached_search(For, Result, Time, Options) :- option(search_in(In), Options, all), option(search_match(Match), Options, summary), cached_search_result(For, In, Match, Result), !, Time = cached. cached_search(For, Result, Time, Options) :- option(search_in(In), Options, all), option(search_match(Match), Options, summary), statistics(cputime, T0), search_doc(For, PerCategory0, Options), order_matches(PerCategory0, Result), statistics(cputime, T1), Time is T1-T0, assertz(cached_search_result(For, In, Match, Result)), prune_search_cache. prune_search_cache :- ( predicate_property(cached_search_result(_,_,_,_), number_of_clauses(Count)), Del is Count - 25, Del > 0 -> forall(between(1,Del,_), retract(cached_search_result(_,_,_,_))) ; true ). page_location(PerCategory, NPages, Offset, Limit, Options) :- option(page(Page), Options, 1), option(per_page(Limit), Options, 25), Offset is (Page-1)*Limit, count_matches(PerCategory, Total), NPages is (Total+Limit-1)//Limit. search_pagination(Options) --> { option(page(Page), Options, 1), option(page_count(NPages), Options, 1) }, html(div(class(pagination), [ \search_prev(Page, Options), span(class(current), ['Page ', Page, ' of ', NPages]), \search_next(NPages, Page, Options) ])). search_prev(Page, _) --> { Page =:= 1 }, !. search_prev(Page, Options) --> { Prev is Page - 1, page_link(Prev, Link, Options) }, html(a(href(Link), '< Prev')). search_next(NPages, Page, _) --> { Page =:= NPages, ! }, []. search_next(_NPages, Page, Options) --> { Next is Page + 1, page_link(Next, Link, Options) }, html(a(href(Link), 'Next >')). page_link(Page, '?'+QueryString, Options) :- option(for(For), Options), option(search_in(In), Options, all), option(search_match(Match), Options, summary), option(resultFormat(Format), Options, summary), uri_query_components(QueryString, [ for(For), in(In), match(Match), resultFormat(Format), page(Page) ]). search_header(_For, _Title, Options) --> { option(header(false), Options) }, !, html_requires(pldoc). search_header(For, Title, Options) --> html_requires(pldoc), doc_links('', [for(For)|Options]), html(h1(class('search-results'), Title)). %! matching_object_table(+Objects, +Options)// is det. % % Show a list of matching objects, similar to a result-set from % search. matching_object_table(Objects, Options) --> { maplist(obj_cat_sec, Objects, Pairs), group_hits(Pairs, Organized), option(format(Format), Options, summary) }, indexed_matches(Format, Organized, Options). obj_cat_sec(Object, Cat-(Section-Object)) :- prolog:doc_object_summary(Object, Cat, Section, _Summary). indexed_matches(Format, PerCategory, Offset, Limit, Options) --> { cat_offset(Offset, _,PerCategory, PerCategory1), cat_limit(Limit, _, PerCategory1, PerCategory2) }, ( { PerCategory2 == PerCategory } -> indexed_matches(Format, PerCategory, Options) ; category_counts(PerCategory, [ showing('Total'), link(category) | Options ]), { delete(Options, cputime(_), Options1) }, category_counts(PerCategory2, [ showing('Showing'), class([showing]) | Options1 ]), search_pagination(Options), matches(Format, PerCategory2, Options) ). %! cat_offset(+Offset, -Remaining, +PerCat0, -PerCat) is det. %! cat_limit(+Limit, -Remaining, +PerCat0, -PerCat) is det. cat_offset(0, 0, PerCat, PerCat) :- !. cat_offset(N, R, [C-H|T], PerCat) :- H = [_-[_|_]|_], !, cat_offset(N, R1, H, H1), ( H1 == [] -> !, cat_offset(R1, R, T, PerCat) ; PerCat = [C-H1|T] ). cat_offset(N, R, [_C-L|T0], PerCat) :- length(L, Len), Left is N-Len, Left > 0, !, cat_offset(Left, R, T0, PerCat). cat_offset(N, 0, [C-L0|T], [C-L|T]) :- !, length(Skip, N), append(Skip, L, L0). cat_offset(N, N, Obj, Obj). cat_limit(0, 0, _PerCat, []) :- !. cat_limit(N, R, [C-H|T], PerCat) :- H = [_-[_|_]|_], !, cat_limit(N, R1, H, H1), ( R1 == 0 -> PerCat = [C-H1] ; PerCat = [C-H|T1], cat_limit(R1, R, T, T1) ). cat_limit(N, R, [C-L|T0], [C-L|T]) :- length(L, Len), More is N - Len, More >= 0, !, cat_limit(More, R, T0, T). cat_limit(N, 0, [C-L0|_], [C-L]) :- !, length(L, N), append(L, _, L0). cat_limit(N, N, [], []). %! order_matches(+PerCat, -Ordered) is det. % % Order matches per category. Each low level object is of the shape % q(Q, Object), where Q is a number between 0 and 1, 1 implying a % perfect fit. order_matches(PerCat0, PerCat) :- maplist(order_category, PerCat0, PerCat). order_category(Cat-PerSection0, Cat-PerSection) :- maplist(order_section, PerSection0, PerSectionTagged), sort(1, >=, PerSectionTagged, Ordered), pairs_values(Ordered, PerSection). order_section(Section-Objects0, Q-(Section-Objects)) :- sort(1, >=, Objects0, Objects), maplist(arg(1), Objects, QList), join_quality(QList, Q). join_quality([], 0). join_quality([Q], Q). join_quality([QH|QL], Q) :- join_quality(QL, QT), Q is 1-(1-QH)*(1-QT). %! indexed_matches(+Format, +PerCategory, +Options)// % % Emit the matches. indexed_matches(Format, PerCategory, Options) --> category_counts(PerCategory, Options), matches(Format, PerCategory, Options). category_counts(PerCategory, Options) --> { count_matches(PerCategory, Matches), option(class(Classes), Options, []), ( PerCategory = [_] -> merge_options([link(false)], Options, Options1) ; Options1 = Options ) }, html([ div(class(['search-counts'|Classes]), [ \category_showing(Options1), Matches, \count_by_category(PerCategory, Options1), \search_time(Options1) ]) ]). count_by_category([Cat-_PerFile], Options) --> !, html(' matches from '), category_link(Cat, Options). count_by_category(PerCategory, Options) --> html(' matches; '), count_by_category_list(PerCategory, Options). count_by_category_list([], _) --> []. count_by_category_list([Cat-PerFile|T], Options) --> { count_category(PerFile, Count) }, html([ \category_link(Cat, Options), ': ', Count ]), ( {T == []} -> [] ; html(', '), count_by_category_list(T, Options) ). count_matches([], 0). count_matches([_-Cat|T], Count) :- count_matches(T, Count0), count_category(Cat, N), Count is Count0 + N. count_category([], 0). count_category([_-Objs|T], Count) :- count_category(T, Count0), length(Objs, N), Count is Count0 + N. category_showing(Options) --> { option(showing(Showing), Options) }, html(span(class('search-showing'), [Showing, :])). category_showing(_) --> []. search_time(Options) --> { option(cputime(Time), Options) }, !, ( { number(Time) } -> html(span(class('search-time'), '(~2f sec.)'-[Time])) ; html(span(class('search-time'), '(~w)'-[Time])) ). search_time(_) --> []. %! matches(+Format, +PerCategory, +Options)// is det % % Display search matches according to Format. % % @param PerCategory List of File-Objects matches(long, PerCategory, Options) --> long_matches_by_type(PerCategory, Options). matches(summary, PerCategory, Options) --> html(table(class(summary), \short_matches_by_type(PerCategory, 1, Options))). long_matches_by_type([], _) --> []. long_matches_by_type([Category-PerFile|T], Options) --> category_header(Category, Options), long_matches(PerFile, Options), long_matches_by_type(T, Options). long_matches([], _) --> []. long_matches([File-Objs|T], Options) --> file_header(File, Options), objects(Objs, Options), long_matches(T, Options). category_header(Category, _Options) --> html(h1(class(category), \category_title(Category))). short_matches_by_type([], _, _) --> []. short_matches_by_type([Category-PerFile|T], Nth, Options) --> category_index_header(Category, Nth, Options), short_matches(PerFile, Options), { succ(Nth, Nth1) }, short_matches_by_type(T, Nth1, Options). short_matches([], _) --> []. short_matches([File-Objs|T], Options) --> file_index_header(File, Options), object_summaries(Objs, File, Options), short_matches(T, Options). category_index_header(Category, Nth, _Options) --> ( { Nth > 1 } -> category_sep('category-top-sep') ; [] ), html(tr(th([class(category), colspan(3)], a(name(Category), \category_title(Category))))), category_sep('category-bottom-sep'). category_sep(Which) --> html(tr(th([class(Which), colspan(3)], &(nbsp)))). category_link(Category, Options) --> { option(link(false), Options) }, !, category_title(Category). category_link(Category, Options) --> { option(link(category), Options), category_link(Category, HREF, Options) }, !, html(a(href(HREF), \category_title(Category))). category_link(Category, _Options) --> { atom_concat(#, Category, HREF) }, html(a(href(HREF), \category_title(Category))). category_link(Category, '?'+QueryString, Options) :- ( category_abbreviation(Category, Abbrev) -> true ; Abbrev = Category ), option(for(For), Options), option(search_match(Match), Options, summary), option(resultFormat(Format), Options, summary), uri_query_components(QueryString, [ for(For), in(Abbrev), match(Match), resultFormat(Format) ]). category_title(Category) --> { prolog:doc_category(Category, _Order, Title) -> true ; Title = Category }, html(Title). %! search_doc(+SearchString, -PerType:list, +Options) is det. % % Return matches of SearchString as Type-PerFile tuples, where PerFile % is a list File-ListOfObjects. search_doc(Search, PerType, Options) :- findall(Tuples, matching_object(Search, Tuples, Options), Tuples0), sort(Tuples0, Tuples), group_hits(Tuples, PerType0), prune_library(PerType0, PerType). group_hits(Tuples, PerType) :- keysort(Tuples, Tuples1), group_pairs_by_key(Tuples1, PerCat0), key_sort_order(PerCat0, PerCat1), keysort(PerCat1, PerCat2), pairs_values(PerCat2, PerCat), group_by_file(PerCat, PerType). key_sort_order([], []). key_sort_order([Cat-ByCat|T0], [Order-(Cat-ByCat)|T]) :- ( prolog:doc_category(Cat, Order, _Title) -> true ; Order = 99 ), key_sort_order(T0, T). group_by_file([], []). group_by_file([Type-Tuples0|T0], [Type-ByFile|T]) :- keysort(Tuples0, Tuples), group_pairs_by_key(Tuples, ByFile), group_by_file(T0, T). %! prune_library(+PerCat0, -PerCat) is det. % % Prune objects from the libary that also appear in the manual. prune_library(PerCat0, PerCat) :- selectchk(library-InLib0, PerCat0, library-InLib, PerCat1), !, ( cat_objects(manual, PerCat0, Manual), cat_objects(packages, PerCat0, Packages), append(Manual, Packages, Objects), sort(Objects, OSet0), maplist(arg(2), OSet0, OSet), % get rid of q(Q,Obj) convlist(prune_section(OSet), InLib0, InLib), InLib \== [] -> PerCat = PerCat1 ; selectchk(library-_, PerCat0, PerCat) ). prune_library(PerCat, PerCat). cat_objects(Cat, PerCat, Objects) :- memberchk(Cat-Sections, PerCat), !, pairs_values(Sections, NestedObjects), append(NestedObjects, Objects). cat_objects(_, _, []). prune_section(Prune, Section-Objects0, Section-Objects) :- exclude(in_set(Prune), Objects0, Objects), Objects \== []. % specific library becomes empty in_set(Prune, q(_Q,Obj)) :- memberchk(Obj, Prune), !. in_set(Prune, q(_Q,_Module:Obj)) :- memberchk(Obj, Prune). %! matching_object(+SearchString, -Object, +Options) is nondet. % % Object matches SearchString. Options include % % - search_in(In) % One of `all`, `app`, `man`. % % - search_match(Match) % One of `name`, `summary` % % @param Object Term of the form File-Item % @tbd Deal with search syntax matching_object(Search, Type-(Section-q(1,Obj)), Options) :- atom_concat(Function, '()', Search), Obj = c(Function), option(search_in(In), Options, all), prolog:doc_object_summary(Obj, Type, Section, _), matching_category(In, Type). matching_object(Search, Type-(Section-q(1,Obj)), Options) :- ( atom_pi(Search, Obj0) -> ground(Obj0) ; catch(atom_to_term(Search, Obj0, _), _, fail), nonvar(Obj0) ), opt_qualify(Obj0, Obj), option(search_in(In), Options, all), prolog:doc_object_summary(Obj, Type, Section, _), matching_category(In, Type). matching_object(Search, Match, Options) :- atom_codes(Search, Codes), phrase(search_spec(For0), Codes), ( For0 = not(_) -> throw(error(bad_search(only_not), _)) ; optimise_search(For0, For), exec_search(For, Match, Options) ). opt_qualify(Obj0, Obj) :- Obj0 = _:_, !, Obj = Obj0. opt_qualify(Obj, Obj). opt_qualify(Obj, _:Obj). %! optimise_search(+Spec, -Optimised) % % Optimise a search specification. Currently only deals with the % simple case of first searching for a negation and then a % positive term. optimise_search(and(not(A0), B0), and(B, not(A))) :- !, optimise_search(A0, A), optimise_search(B0, B). optimise_search(A, A). %! exec_search(+Spec, -Match, +Options) is nondet. % % Spec is one of % % - and(Spec, Spec) % Intersection of the specification % - not(Spec) % Negation of the specification % - quoted(Tokens) % A quoted list of tokens. exec_search(Spec, Match, Options) :- exec_search(Spec, Match0, Q, Options), add_quality(Match0, Q, Match). add_quality(Type-(Section-Obj), Q, Type-(Section-q(Q,Obj))). exec_search(and(A, B), Match, Q, Options) :- !, exec_search(A, Match, Q1, Options), exec_search(B, Match, Q2, Options), Q is 1-((1-Q1)*(1-Q2)). exec_search(Search, Type-(Section-Obj), Q, Options) :- option(search_in(In), Options, all), option(search_match(Match), Options, summary), option(private(Public), Options, true), prolog:doc_object_summary(Obj, Type, Section, Summary), matching_category(In, Type), match_private(Public, Obj), ( Search = not(For) -> State = s(0), \+ ( match_object(For, Obj, Summary, Match, Q), nb_setarg(1, State, Q) ), arg(1, State, Q) ; match_object(Search, Obj, Summary, Match, Q) ). matching_category(all, _). matching_category(noapp, Category) :- !, Category \== application. matching_category(Category, Category). matching_category(Abbrev, Category) :- category_abbreviation(Category, Abbrev). category_abbreviation(application, app). category_abbreviation(manual, man). category_abbreviation(library, lib). category_abbreviation(packages, pack). category_abbreviation(wiki, wiki). match_private(true, _). match_private(false, Object) :- ( Object = (Module:PI) -> current_module(Module), pi_head(PI, Head), ( predicate_property(Module:Head, exported) -> true ; predicate_property(Module:Head, multifile) -> true ; predicate_property(Module:Head, public) ) ; true ). pi_head(Name/Arity, Head) :- functor(Head, Name, Arity). pi_head(Name//Arity, Head) :- Arity1 is Arity+ 2, functor(Head, Name, Arity1). %! search_spec(-Search)// is det. % % Break a search string from the user into a logical expression. search_spec(Spec) --> blanks, prim_search_spec(A), blanks, ( eos -> { Spec = A } ; search_spec(B) -> { Spec = and(A,B) } ). prim_search_spec(quoted(Quoted)) --> "\"", string(Codes), "\"", !, { tokenize_atom(Codes, Quoted) }. prim_search_spec(Spec) --> nonblanks(Codes), { Codes = [0'-,C0|Rest], code_type(C0, csym) -> atom_codes(Word, [C0|Rest]), Spec = not(Word) ; Codes \== [], atom_codes(Spec, Codes) }. %! object_summary(?Object, ?Category, ?Section, ?Summary) is nondet. % % True if Object is summarised by Summary. This multifile % predicate can be extended with other search mechanisms. The % returned objects must be handled by object_summaries//2 and % objects//2. % % @param Category Atom describing the source. % @param Section Reference to the context of Object. prolog:doc_object_summary(Obj, Category, File, Summary) :- once(prolog_object(Obj)), current_prolog_flag(home, SWI), doc_comment(Obj0, File:_Line, Summary, _Comment), ( is_list(Obj0) -> member(Obj, Obj0) ; Obj = Obj0 ), Obj \= _:module(_Title), % HACK. See ref_object//1 ( sub_atom(File, 0, _, _, SWI) -> Category = library ; Category = application ). prolog_object(Var) :- var(Var), !. prolog_object(_/_). prolog_object(_//_). prolog_object(_:_/_). prolog_object(_:_//_). prolog_object(module(_)). %! doc_category(Name, SortOrder, Description) is nondet. % % Describe the various categories of search results. Used to % create the category headers as well as the advanced search % dialog. % % @param SortOrder Ranges 0..100. Lower values come first prolog:doc_category(application, 20, 'Application'). prolog:doc_category(library, 80, 'System Libraries'). /******************************* * UTIL * *******************************/ %! match_object(+For, +Object, +Summary, +How, -Quality) is semidet. % % True when Object with summary text Summary matches For acording to % How. % % @arg For is either a token (atom) or a term quoted(Tokens), where % `Tokens` is a list of atoms. % @arg How is one of `name` or `summary` % @arg Quality is a number in the range 0..1, where 1 means a strong % match. match_object(For, Object, Summary, How, Quality) :- ( doc_object_identifier(Object, Identitier), identifier_match_quality(For, Identitier, Quality) -> debug(search(rank), 'Rank "~w" in identifier "~w": ~q', [For, Identitier, Quality]) ; How == summary, summary_match_quality(For, Summary, Quality), debug(search(rank), 'Rank "~w" in summary "~w": ~q', [For, Summary, Quality]) ). summary_match_quality(For, Summary, Q) :- tokenize_atom(Summary, Tokens0), exclude(is_punctuation, Tokens0, Tokens), Tokens \== [], token_match_quality(summary, For, Tokens, Q0), Q is Q0/2. is_punctuation(Token) :- atom_length(Token, 1), char_type(Token, punct). identifier_match_quality(Identifier, Identifier, 1) :- !. identifier_match_quality(For, Identifier, Q) :- dwim_match(For, Identifier, _), !, Q = 0.8. identifier_match_quality(For, Identifier, Q) :- identifier_parts(Identifier, Parts), Parts \== [], token_match_quality(identifier, For, Parts, Q). token_match_quality(_How, quoted(Tokens), Parts, Q) :- !, append(Tokens, _, All), append(_, All, Parts), Q = 1. token_match_quality(How, For, Parts, Q) :- length(Parts, Len), ( memberchk(For, Parts) -> Q0 = 1 ; porter_stem(For, Stem), member(Part, Parts), porter_stem(Part, Stem) -> Q0 = 0.9 ; How == summary, member(Part, Parts), sub_atom_icasechk(Part, _, For), identifier_parts(Part, SubParts), token_match_quality(identifier, For, SubParts, Q00) -> Q0 is Q00/2 ; How == summary, member(Part, Parts), sub_atom_icasechk(Part, 0, For), is_numbered_var(Part, For) -> Q0 is 0.9 ; doc_related_word(For, Word, Distance), memberchk(Word, Parts) -> Q0 = Distance ), Q is Q0/Len. is_numbered_var(VarName, Search) :- atom_length(Search, Len), sub_string(VarName, Len, _, 0, NS), number_string(_, NS), sub_atom(VarName, 0, 1, _, First), char_type(First, prolog_var_start).