Module:Check for deprecated 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
 -- on the list
 localp={}

 localfunctiontrim(s)
 returns:match('^%s*(.-)%s*$')
 end

 localfunctionisnotempty(s)
 returnsandtrim(s)~=''
 end

 functionp.check(frame)
 -- create the table of deprecated values and their matching new value
 localargs=frame.args
 localdep_values={}
 fork,vinpairs(args)do
 ifk=='ignoreblank'ork=='preview'ork=='deprecated'thenelse
 dep_values[k]=v
 end
 end

 -- loop over the parent args and see if any are deprecated
 localvalues={}
 localignoreblank=isnotempty(frame.args['ignoreblank'])
 localpargs=frame:getParent().args
 fork,vinpairs(pargs)do
 ifignoreblankthen
 ifdep_values[k]andv~=''then
 table.insert(values,k)
 end
 else
 ifdep_values[k]then
 table.insert(values,k)
 end
 end
 end

 -- add results to the output tables
 localres={}
 if#values>0then
 localpreview=frame.args['preview']or
 'Page using [['..frame:getParent():getTitle()..']] with deprecated parameter _VALUE_'
 ifisnotempty(preview)then
 preview=require('Module:If preview')._warning({
 preview
 })
 end
 -- Kind of dangerous to trust that this is never nil, but I guess it's
 -- preferable to display that the use of the module is broken rather than
 -- have some sort of tracking category for pages which have an unknown
 -- parent tracking template.
 localcategory=frame.args['category']
 fork,vinpairs(values)do
 localc=category:gsub('_VALUE_',v)
 table.insert(res,c)
 ifv==''then
 -- Fix odd bug for | = which gets stripped to the empty string
 -- and breaks category links
 v=' '
 end
 localp=preview:gsub(
 '_VALUE_',
 '"'..v..'". Replace with "'..dep_values[v]..'".'
 )
 table.insert(res,p)
 end
 end

 returntable.concat(res)
 end

 returnp