30:[] 2e:{"title":"Hello, Stockfish","cells":[{"id":0,"value":"md`# Hello, Stockfish\n\nSaying hello to the [Stockfish chess engine](https://github.com/nmrugg/stockfish.js). Stockfish uses a Web Worker, so to get around cross-origin restrictions, the script is first fetched.`","pinned":false,"hidden":false,"mode":"ojs"},{"id":25,"value":"md` \nuci protocal: http://wbec-ridderkerk.nl/html/UCIProtocol.html \nmore uci: https://www.chessprogramming.org/UCI \nsf interface: https://gist.github.com/aliostad/f4470274f39d29b788c1b09519e67372 \n`","pinned":false,"hidden":false,"mode":"ojs"},{"id":5,"value":"stockfish = {\n \n const workerScript = await require.resolve(\"stockfish@10/src/stockfish.asm.js\")\n .then(fetch)\n .then(response => response.blob())\n .then(blob => URL.createObjectURL(blob, {type: \"text/javascript\"}))\n ;\n \n return new Worker(workerScript);\n\n}","pinned":false,"hidden":false,"mode":"ojs"},{"id":14,"value":"async function ask(stockfish, command, params=\"\") {\n \n let \n resolve, \n idx = (\"0000\" + trigger).slice(-4),\n message = command + \" \" + params,\n promise = new Promise(r => resolve = r),\n waitfor = ({\n 'go': 'bestmove',\n 'uci': 'uciok',\n 'isready': 'readyok',\n 'position': 'NOP',\n 'ucinewgame': 'NOP',\n 'd': 'Legal'\n })[command]\n ;\n \n stockfish.onmessage = e => {\n \n console.log( e.data );\n\n if (e.data.includes(waitfor)) {\n messages.push(idx + ' <== ' + e.data, '');\n mutable trigger += 1; \n resolve(e.data);\n \n } else {\n messages.push(idx + ' ' + e.data);\n \n }\n\n }\n ;\n \n if (!waitfor) throw new Error(\"command not available\", command);\n \n console.log( message );\n messages.push(idx + ' ==> ' + message);\n (waitfor === 'NOP') && messages.push('');\n mutable trigger += 1; \n \n stockfish.postMessage( message );\n \n return promise;\n \n}","pinned":true,"hidden":false,"mode":"ojs"},{"id":274,"value":"mutable messages = [];","pinned":false,"hidden":false,"mode":"ojs"},{"id":276,"value":"mutable trigger = 0;","pinned":false,"hidden":false,"mode":"ojs"},{"id":123,"value":"{ trigger; return html`

${ messages.slice(-30).map( v => `${v}
` ) }

`}","pinned":true,"hidden":false,"mode":"ojs"},{"id":334,"value":"{\n const btnReady = html``;\n btnReady.onclick = () => ask(stockfish, \"isready\");\n\n const btnUCI = html``;\n btnUCI.onclick = () => ask(stockfish, \"uci\");\n\n const btnGO = html``;\n btnGO.onclick = () => ask(stockfish, \"go\", \"depth 3\");\n \n const btnNewGame = html``;\n btnNewGame.onclick = () => ask(stockfish, \"ucinewgame\");\n \n const btnFen = html``;\n btnFen.onclick = () => ask(stockfish, \"position\", \"fen \" + fens[1]);\n \n const btnDisplay = html``;\n btnDisplay.onclick = () => ask(stockfish, \"d\");\n \n return html`${btnReady} ${btnUCI} ${btnNewGame} ${btnFen} ${btnGO} ${btnDisplay} `;\n}","pinned":false,"hidden":false,"mode":"ojs"},{"id":415,"value":"fens = [\n 'rnbqkbnr/pppppppp/8/8/8/8/PPPPPPPP/RNBQKBNR w KQkq - 0 1',\n 'N7/P3pk1p/3p2p1/r4p2/8/4b2B/4P1KP/1R6 w - - 0 34',\n '7K/8/k1P5/7p/8/8/8/8'\n];","pinned":false,"hidden":false,"mode":"ojs"}],"files":"$W30","stdlib":"1","titling":"auto"}