Module:Chess from pgn explained

pgn = require('module:pgn')

local function moveToIndex(move) if not move:match('^%d+[dl]$') then return -1 end -- not a move local num, color = move:match('(%d+)([dl])') return num * 2 + (color

'd' and 1 or 0)end

local function indexToMove(index) return string.format('%d%s', math.floor(index / 2), index % 2

0 and 'l' or 'd')end function display_game(frame) local args = frame:getParent.args for k, v in pairs(frame.args) do args[k] = v end local game = args['pgn'] if not game then error('must have "pgn" parameter') end local moves = pgn.pgn2fen(game) local template = args['template'] if not template then error('must have "template" parameter') end local tmTable = local hydrate = function(index, comment) local temp = template:gsub('%$fen%$', moves[index]) temp = temp:gsub('%$comment%$', comment) temp = temp:gsub('%$move%$', indexToMove(index)) table.insert(tmTable,) end template = mw.text.unstripNoWiki(template) for arg, val in pairs(args) do -- collect boards of the form "12l = comment" local index = moveToIndex(arg) if index >= 0 then hydrate(index, val) end end

for arg, val in pairs(args) do -- collect boards of the form "| from1 = 7d | to1 = 8l | comments1 = if arg:match('^from%d+$') then local hunk = arg:match(('^from(%d+)$')) toMove = args['to' .. hunk] if not toMove then error (string.format('parameter %s exists, but no parameter to%s', arg, hunk)) end local fromIndex = moveToIndex(val) if fromIndex < 0 then error(string.format('malformed value for parameter %s', arg)) end local toIndex = moveToIndex(toMove) if toIndex < 0 then error(string.format('malformed value for parameter to%s', hunk)) end local comments = local commentsVal = args['comments' .. hunk] or for comment in commentsVal:gmatch('') do table.insert(comments, comment) end for index = fromIndex, toIndex do hydrate(index, table.remove(comments, 1) or ) end end end table.sort(tmTable, function(a, b) return a[1] < b[1] end) local res = for _, item in ipairs(tmTable) do res = res .. frame:preprocess(item[2]) end return resend

return