This module may be appended to a template to check for uses of unknown parameters.

{{#invoke:check for unknown parameters|check|unknown=[[Category:Some tracking category]]|arg1|arg2|arg3|argN}}

or to sort the entries in the tracking category by parameter with a preview error message

{{#invoke:check for unknown parameters|check|unknown=[[Category:Some tracking category|_VALUE_]]|preview=unknown parameter "_VALUE_"|arg1|arg2|...|argN}}

or for an explicit red error message

{{#invoke:check for unknown parameters|check|unknown=<span>Sorry, I don't recognize _VALUE_</span>|arg1|arg2|...|argN}}

Here,arg1,arg2, ...,argN, are the known parameters. Unnamed (positional) parameters can be added too:|1|2|argname1|argname2|.... Any parameter which is used, but not on this list, will cause the module to return whatever is passed with theunknown parameter. The_VALUE_ keyword, if used, will be changed to the name of the parameter. This is useful for either sorting the entries in a tracking category, or for provide more explicit information.

By default, the module makes no distinction between a defined-but-blank parameter and a non-blank parameter. That is, both unlisted|foo=x and|foo= are reported. To only track non-blank parameters use|ignoreblank=1.

By default, the module ignores blank positional parameters. That is, an unlisted|2= is ignored. Toinclude blank positional parameters in the tracking use|showblankpositional=1.

This module supportsLua patterns (similar toregular expressions), which are useful when there are many known parameters which use a systematic pattern. For example,template:infobox3cols uses

| regexp1 = header[%d][%d]*| regexp2 = label[%d][%d]*| regexp3 = data[%d][%d]*[abc]?| regexp4 = class[%d][%d]*[abc]?| regexp5 = rowclass[%d][%d]*| regexp6 = rowstyle[%d][%d]*| regexp7 = rowcellstyle[%d][%d]*

to match all parameters of the formheaderNUM,labelNUM,dataNUM,dataNUMa,dataNUMb,dataNUMc, ...,rowcellstyleNUM, where NUM is a string of digits.

{{Infobox| above = {{{name|}}}| label1 = Height| data1 = {{{height|}}}| label2 = Weight| data2 = {{{weight|}}}| label3 = Website| data3 = {{{website|}}}}}<!--   end infobox, start tracking-->{{#invoke:Check for unknown parameters|check| unknown = {{main other|[[Category:Some tracking category|_VALUE_]]}}| preview = unknown parameter "_VALUE_"| name| height | weight| website}}

• {{Math}}
• Template:Clc (category page can have header {{Unknown parameters category}})
• Module:Check for deprecated parameters – similar module that checks for deprecated parameters
• Module:Check for clobbered parameters – module that checks for conflicting parameters
• Module:TemplatePar – similar function (originally from dewiki)
• Template:Parameters andModule:Parameters – generates a list of parameter names for a given template
• Project:TemplateData based template parameter validation
  • he:Module:ParamValidator – parameter validation system on hewiki, relies on TemplateData. module doc in English. checks the following:
    • use of undeclared parameters
    • use of parameters marked in templatedata "deprecated"
    • mistyped (mainly, parameters declared in templatedata as "number" receiving non-numerical value)
    • missing parameters marked in TemplateData as "required"
    • understands aliases, and warns when more than one alias of a parameter is used
  • cs:Module:CheckParameters – another parameter check system on cswiki that relies on TemplateData
• s:cs:Module:MonitorTemplateArguments – a template parameter monitoring system based on tracking categories
• User:Bamyers99/TemplateParametersTool - A tool for checking usage of template parameters

-- This module may be used to compare the arguments passed to the parent-- with a list of arguments, returning a specified result if an argument is-- not on the listlocalp={}localfunctiontrim(s)returns:match('^%s*(.-)%s*$')endlocalfunctionisnotempty(s)returnsands:match('%S')endlocalfunctionclean(text)-- Return text cleaned for display and truncated if too long.-- Strip markers are replaced with dummy text representing the original wikitext.localpos,truncatedlocalfunctiontruncate(text)iftruncatedthenreturn''endifmw.ustring.len(text)>25thentruncated=truetext=mw.ustring.sub(text,1,25)..'...'endreturnmw.text.nowiki(text)endlocalparts={}forbefore,tag,remainderintext:gmatch('([^\127]*)\127[^\127]*%-(%l+)%-[^\127]*\127()')dopos=remaindertable.insert(parts,truncate(before)..'<'..tag..'>...</'..tag..'>')endtable.insert(parts,truncate(text:sub(posor1)))returntable.concat(parts)endfunctionp._check(args,pargs)iftype(args)~="table"ortype(pargs)~="table"then-- TODO: error handlingreturnend-- create the list of known args, regular expressions, and the return stringlocalknownargs={}localregexps={}fork,vinpairs(args)doiftype(k)=='number'thenv=trim(v)knownargs[v]=1elseifk:find('^regexp[1-9][0-9]*$')thentable.insert(regexps,'^'..v..'$')endend-- loop over the parent args, and make sure they are on the listlocalignoreblank=isnotempty(args['ignoreblank'])localshowblankpos=isnotempty(args['showblankpositional'])localvalues={}fork,vinpairs(pargs)doiftype(k)=='string'andknownargs[k]==nilthenlocalknownflag=falsefor_,regexpinipairs(regexps)doifmw.ustring.match(k,regexp)thenknownflag=truebreakendendifnotknownflagand(notignoreblankorisnotempty(v))thentable.insert(values,clean(k))endelseiftype(k)=='number'andknownargs[tostring(k)]==nilthenlocalknownflag=falsefor_,regexpinipairs(regexps)doifmw.ustring.match(tostring(k),regexp)thenknownflag=truebreakendendifnotknownflagand(showblankposorisnotempty(v))thentable.insert(values,k..' = '..clean(v))endendend-- add results to the output tableslocalres={}if#values>0thenlocalunknown_text=args['unknown']or'Found _VALUE_, 'ifmw.getCurrentFrame():preprocess("{{REVISIONID}}")==""thenlocalpreview_text=args['preview']ifisnotempty(preview_text)thenpreview_text=require('Module:If preview')._warning({preview_text})elseifpreview==nilthenpreview_text=unknown_textendunknown_text=preview_textendfor_,vinpairs(values)do-- Fix odd bug for | = which gets stripped to the empty string and-- breaks category linksifv==''thenv=' 'end-- avoid error with v = 'example%2' ("invalid capture index")localr=unknown_text:gsub('_VALUE_',{_VALUE_=v})table.insert(res,r)endendreturntable.concat(res)endfunctionp.check(frame)localargs=frame.argslocalpargs=frame:getParent().argsreturnp._check(args,pargs)endreturnp