Module:Wikidata/Analyse transitive

La documentation pour ce module peut être créée à Module:Wikidata/Analyse transitive/Documentation

-- Helpers for queries using transitive properties

local p = {}
local wd = require "Module:Wikidata"

local function getids(item, query) 
	query.excludespecial = true
	query.displayformat = 'raw'
	query.entity = item
	return wd.stringTable(query)
end

local function alreadyHere(searchset, val)
	for i, j in pairs(searchset) do
		if val == j then
			return true
		end
	end
	return false
end

-- add new items to a list, avoiding duplicates
local function addnewvalues(olditems, newitems, maxnum, stopval)
	if not newitems then
		return olditems
	end
	for _, qid in pairs(newitems) do
		if stopval and (qid == stopval) then
			table.insert(olditems, qid)
		return olditems
		end
		if maxnum and (#olditems >= maxnum) then
			return olditems
		end
		if not alreadyHere(olditems, qid) then
			table.insert(olditems, qid)
		end
	end
	return olditems
end

-- recursively adds a list of qid to an existing list, based on the results of a query
function p.addVals(list, query, maxdepth, maxnodes, stopval)
	maxdepth = maxdepth or 10
	maxnodes = maxnodes or 100
	if (maxdepth < 0) then
		return list
	end
	if stopval and alreadyHere(list, stopval) then
		return list
	end
	local origsize = #list
	for i = 1, origsize do
	-- tried a  "checkpos" param instead of starting to 1 each time, but no impact on performance
	local candidates = getids(list[i], query)
	list = addnewvalues(list, candidates, maxnum, stopval)
	if list[#list] == stopval then
		return list
	end
	if #list >= maxnodes then
		return list
	end
	end
	if (#list == origsize) then
		return list
	end
	return p.addVals(list, query, maxdepth - 1, maxnodes, stopval, origsize + 1)
end

-- returns a list of items transitively matching a query (orig item is not included in the list)
function p.transitiveVals(item, query, maxdepth, maxnodes, stopval)
	maxdepth = maxdepth or 10
	local vals = getids(item, query)
	if not vals then
		return nil
	end
return p.addVals(vals, query, maxdepth - 1, maxnodes, stopval)
end

-- returns true if an item is the value of a query, transitively
function p.inTransitiveVals(searchedval, sourceval, query, maxdepth, maxnodes )
	local vals = p.transitiveVals(sourceval, query, maxdepth, maxnodes, searchedval )
	if vals and vals[#vals] == searchedval then
		return true
	end
	return false
end

-- returns true if an item is a superclass of another, based on P279
function p.isSubclass(class, item, maxdepth)
	local query = {property = 'P279'}
	if class == item then -- item is a subclass of itself iff it is a class
	if getids(item, query) then
		return true
	end
	return false
	end
	return p.inTransitiveVals(class, item, query, maxdepth )
end

-- returns true if one of the best ranked P31 values of an item is the target or a subclass of the target
-- rank = 'valid' would seem to make sense, but it would need to check for date qualifiers as some P31 values have begin or end date
function p.isInstance(targetclass, item, maxdepth)
	maxdepth = maxdepth or 10
	local directclasses = p.transitiveVals(item, {property = 'P31'}, 1)
	if not directclasses then
	return false
	end
	for i, class in pairs(directclasses) do
		if p.isSubclass(targetclass, class, maxdepth - 1) then
			return true
		end
	end
	return false
end

return p