Game of Life JavaScript: Commit a Whole Generation

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<body class="game"><main><header><div class="eyebrow">Original interactive state lab</div><h1>Game of Life JavaScript: Commit a Whole Generation</h1><p>Updating one cell before counting its neighbor makes the answer depend on traversal order. <mark>Read one unchanged grid and commit another</mark> so the generation is simultaneous.</p></header>
<nav><button type="button" id="step">Step</button><button type="button" id="run">Run</button><button type="button" id="pause">Pause</button><button type="button" id="blinker">Blinker</button><button type="button" id="block">Block</button><button type="button" id="corner">Isolated corner</button><button type="button" id="reset">Reset seed</button></nav><div id="board" class="board five"></div><p id="result" class="result" role="status"></p><div id="ledger" class="ledger"></div><p>Paused cell activation inspects and toggles the cell, then records that edited grid as the new reset seed.</p><section><h2>Last committed transition</h2><div id="transition">No generation committed.</div></section>
<footer>A paused edit creates a new reset seed and clears the previous transition.</footer></main><script>
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