local p = { }
p.fill = function ( frame )
    -- Template filling
    local t = mw.title.getCurrentTitle()
    local r, scope
    if t.namespace == 10 then
        scope = "doc"
    elseif t.namespace == 14 then
        scope = "cat"
    end
    if scope then
        local lucky, c = pcall( mw.loadJsonData, "Module:Babel.json" )
        if type( c ) == "table"  and
           type( c[ scope ] ) == "table" then
            local s = t.text
            local slang, start
            c = c[ scope ]
            if type( c.sub ) == "string" then
                start, slang = s:match( c.sub )
            end
            if not start  and
               type( c.special ) == "string" then
                start, slang = s:match( c.special )
            end
            if not start  and
               type( c.slang ) == "string" then
                start, slang = s:match( c.slang )
            end
            if start  and
               type( c.source ) == "string" then
                local n = start:len() + slang:len()
                local params, score
                if s:len() > n then
                    s = s:sub( n + 1 )
                    if type( c.standard ) == "string" then
                        score = s:match( c.standard )
                    end
                    if not score  and
                       type( c.superior ) == "string" then
                        score = s:match( c.superior )
                    end
                end
                params = { lang  = slang,
                           level = score or "N" }
                s = frame:expandTemplate{ title = c.source,
                                          args  = params }
                if type( s ) == "string" then
                    r = s
                end
            end
        end
    end
    return r or ""
end -- p.fill
return p