# Module:Namespace detect

---
-- --
-- NAMESPACE DETECT --
-- --
-- This module implements the template in Lua, with a few --
-- improvements: all namespaces and all namespace aliases are supported, and namespace --
-- names are detected automatically for the local wiki. The module can also use the --
-- corresponding subject namespace value if it is used on a talk page. Parameter names --
-- can be configured for different wikis by altering the values in the "cfg" table. --
-- --
---  
---
-- Configuration data --
-- Language-specific parameter names can be set here. --
---  
local cfg = {}  
-- This parameter displays content for the main namespace:
cfg.main = 'main'  
-- This parameter displays in talk namespaces:
cfg.talk = 'talk'  
-- This parameter displays content for "other" namespaces (namespaces for which
-- parameters have not been specified, or for when cfg.demospace is set to cfg.other):
cfg.other = 'other'  
-- This parameter makes talk pages behave as though they are the corresponding subject namespace.
-- Note that this parameter is used with Module:Yesno. Edit that module to change
-- the default values of "yes", "no", etc.
cfg.subjectns = 'subjectns'  
-- This parameter sets a demonstration namespace:
cfg.demospace = 'demospace'  
-- This parameter sets a specific page to compare:
cfg.page = 'page'  
-- The header for the namespace column in the wikitable containing the list of possible subject-space parameters.
cfg.wikitableNamespaceHeader = 'Namespace'  
-- The header for the wikitable containing the list of possible subject-space parameters.
cfg.wikitableAliasesHeader = 'Aliases'  
---
-- End configuration data --
---  
local yesno = require('Module:Yesno')  
local p = {}  
function p.getPageObject(page)
-- Get the page object, passing the function through pcall in case we are over the expensive function count limit.
if page then
local noError, pageObject = pcall(mw.title.new, page)
if not noError then
return nil
else
return pageObject
end
else
return mw.title.getCurrentTitle
end
end  
function p.getParamMappings
--[[ Returns a table of how parameter names map to namespace names. The keys are the actual namespace
names, in lower case, and the values are the possible parameter names for that namespace, also in
lower case. The table entries are structured like this:
{
[''] = {'main'},
['wikipedia'] = {'wikipedia', 'project', 'wp'},
...
}
local mappings = {}
mappings[mw.ustring.lower(mw.site.namespaces[0].name)] = {cfg.main}
mappings[cfg.talk] = {cfg.talk}
for nsid, ns in pairs(mw.site.subjectNamespaces) do
if nsid ~= 0 then -- Exclude main namespace.
local nsname = mw.ustring.lower(ns.name)
local canonicalName = mw.ustring.lower(ns.canonicalName)
mappings[nsname] = {nsname}
if canonicalName ~= nsname then
table.insert(mappings[nsname], canonicalName)
end
for _, alias in ipairs(ns.aliases) do
table.insert(mappings[nsname], mw.ustring.lower(alias))
end
end
end
return mappings
end  
local function getNamespace(args)
-- Gets the namespace name from the page object.
local page = args[cfg.page]
local demospace = args[cfg.demospace]
local subjectns = args[cfg.subjectns]
local ret
if demospace then
-- Handle "demospace = main" properly.
if mw.ustring.lower(demospace) == cfg.main then
ret = mw.site.namespaces[0].name
else
ret = demospace
end
else
local pageObject = p.getPageObject(page)
if pageObject then
if pageObject.isTalkPage then
-- If cfg.subjectns is set, get the subject namespace, otherwise use cfg.talk.
if yesno(subjectns) then
ret = mw.site.namespaces[pageObject.namespace].subject.name
else
ret = cfg.talk
end
else
ret = pageObject.nsText
end
else
return nil -- return nil if the page object doesn't exist.
end
end
ret = mw.ustring.gsub(ret, '_', ' ')
return mw.ustring.lower(ret)
end  
function p._main(args)
-- Get the namespace to compare the parameters to, and the parameter mapping table.
local namespace = getNamespace(args)
local mappings = p.getParamMappings
-- Check for any matches in the namespace arguments. The order we check them doesn't matter,
-- as there can only be one match.
for ns, params in pairs(mappings) do
if ns == namespace then
-- Check all aliases for matches. The default local namespace is checked first, as
-- checked these before alias names.
for _, param in ipairs(params) do
if args[param] ~= nil then
return args[param]
end
end
end
end
-- If there were no matches, return parameters for other namespaces. This happens if there
-- was no text specified for the namespace that was detected or if the demospace parameter
-- is not a valid namespace. Note that the parameter for the detected namespace must be
-- completely absent for this to happen, not merely blank.
if args[cfg.other] ~= nil then
return args[cfg.other]
end
end  
function p.main
-- If called via #invoke, use the args passed into the invoking template, or the args
-- passed to #invoke if any exist. Otherwise assume args are being passed directly in.
local origArgs
if == mw.getCurrentFrame then
origArgs = :getParent.args
for k, v in pairs(.args) do
origArgs = .args
break
end
else
origArgs =
end
-- Trim whitespace and remove blank arguments for demospace and page parameters.
local args = {}
for k, v in pairs(origArgs) do
if type(v) == 'string' then
v = mw.text.trim(v) -- Trim whitespace.
end
if k == cfg.demospace or k == cfg.page then
if v ~= '' then
args[k] = v
end
else
args[k] = v
end
end
return p._main(args)
end  
function p.table
-- Create a wikitable of all subject namespace parameters, for documentation purposes. The talk
parameter is optional, in case it needs to be excluded in the documentation.  
local useTalk = type == 'table' and type(.args) == 'table' and .args.talk == 'yes' -- Whether to use the talk parameter.
local mappings = p.getParamMappings
-- Start the wikitable.
local ret = '{|'
.. '\n|-'
.. '\n! ' .. cfg.wikitableNamespaceHeader
.. '\n! ' .. cfg.wikitableAliasesHeader  
-- Generate the row for the main namespace, as we want this to be first in the list.
ret = ret .. '\n|-'
.. '\n| <code>' .. cfg.main .. '</code>'
.. '\n|'
if useTalk then
ret = ret .. '\n|-'
.. '\n| <code>' .. cfg.talk .. '</code>'
.. '\n|'
end
-- Enclose all parameter names in <code> tags.
for ns, params in pairs(mappings) do
if ns ~= mw.site.namespaces[0].name then
for i, param in ipairs(params) do
mappings[ns][i] = '<code>' .. param .. '</code>'
end
end
end
-- Generate the other wikitable rows.
for ns, params in pairs(mappings) do
if ns ~= mw.site.namespaces[0].name then -- Ignore the main namespace.
ret = ret .. '\n|-'
.. '\n| ' .. params[1]
.. '\n| ' .. table.concat(params, ', ', 2)
end
end
-- End the wikitable.
ret = ret .. '\n|-'
.. '\n|}'
return ret
end  
return p