[{"data":1,"prerenderedAt":-1},["ShallowReactive",2],{"playground-react-weekly-form-actions-pending-state":3,"verticals":19,"search-suggestions":58},{"slug":4,"title":5,"summary":6,"html":7,"css":8,"js":9,"config":10,"doc":13},"react-weekly-form-actions-pending-state","React form Actions — pending state playground",null,"\u003Cdiv class=\"pg\">\n    \u003Ch1 class=\"pg-title\">🎮 Pending State: Hand-Rolled vs. React Actions\u003C\u002Fh1>\n    \u003Cp class=\"pg-sub\">\n      Same fake save button, two implementations. Trigger a failure and watch what\n      each one does to its own \"disabled\" flag — then flip on the throw trap and\n      watch the real \u003Ccode>useActionState\u003C\u002Fcode> form get caught by a real Error Boundary.\n    \u003C\u002Fp>\n\n    \u003Cdiv class=\"panel\">\n      \u003Cdiv class=\"panel-label\">\u003Cspan class=\"n\">1\u003C\u002Fspan> Controls\u003C\u002Fdiv>\n      \u003Cdiv class=\"btn-row\">\n        \u003Clabel class=\"toggle\">\n          \u003Cinput type=\"checkbox\" id=\"failToggle\" \u002F>\u003Cspan class=\"switch\">\u003C\u002Fspan>\n          \u003Cspan>Simulate a failing request\u003C\u002Fspan>\n        \u003C\u002Flabel>\n        \u003Clabel class=\"toggle\">\n          \u003Cinput type=\"checkbox\" id=\"throwToggle\" \u002F>\u003Cspan class=\"switch\">\u003C\u002Fspan>\n          \u003Cspan>React panel: throw instead of returning the error\u003C\u002Fspan>\n        \u003C\u002Flabel>\n      \u003C\u002Fdiv>\n      \u003Cdiv class=\"btn-row\" style=\"margin-top:12px\">\n        \u003Cbutton class=\"btn ghost sm\" id=\"resetAll\">Reset both panels\u003C\u002Fbutton>\n      \u003C\u002Fdiv>\n      \u003Cp class=\"hint\">Both panels share the same \"simulate a failing request\" flag. Submit each side separately to compare.\u003C\u002Fp>\n    \u003C\u002Fdiv>\n\n    \u003Cdiv class=\"cols\">\n      \u003Cdiv class=\"panel\">\n        \u003Cdiv class=\"col-title\">Hand-rolled \u003Ccode>useState\u003C\u002Fcode> \u003Cspan class=\"tag\">the way most of us wrote it\u003C\u002Fspan>\u003C\u002Fdiv>\n        \u003Cdiv class=\"btn-row\">\n          \u003Cinput id=\"manualName\" placeholder=\"name\" value=\"Ada\" style=\"background:var(--card);border:1px solid var(--line);border-radius:var(--radius-sm);padding:6px 9px;color:inherit;font:inherit\" \u002F>\n          \u003Cbutton class=\"btn primary\" id=\"manualSubmit\">Save\u003C\u002Fbutton>\n        \u003C\u002Fdiv>\n        \u003Cdiv class=\"status\" id=\"manualStatus\" style=\"margin-top:12px\">\n          \u003Cspan class=\"dot info\" id=\"manualDot\">\u003C\u002Fspan>\u003Cspan id=\"manualStatusText\">Ready.\u003C\u002Fspan>\n        \u003C\u002Fdiv>\n        \u003Cdiv class=\"log\" id=\"manualLog\" style=\"margin-top:10px; max-height:120px; overflow:auto\">\u003C\u002Fdiv>\n      \u003C\u002Fdiv>\n\n      \u003Cdiv class=\"panel\">\n        \u003Cdiv class=\"col-title\">\u003Ccode>useActionState\u003C\u002Fcode> \u003Cspan class=\"tag\">real React 19\u003C\u002Fspan>\u003C\u002Fdiv>\n        \u003Cdiv id=\"reactRoot\">\u003C\u002Fdiv>\n        \u003Cdiv class=\"log\" id=\"reactLog\" style=\"margin-top:10px; max-height:120px; overflow:auto\">\u003C\u002Fdiv>\n      \u003C\u002Fdiv>\n    \u003C\u002Fdiv>\n\n    \u003Cdiv class=\"banner info show\" id=\"cdnBanner\">\n      Loading React 19.2 from esm.sh… if this banner doesn't go away, the CDN is\n      blocked from wherever you're viewing this — the manual panel on the left\n      still works, since it's plain JavaScript.\n    \u003C\u002Fdiv>\n  \u003C\u002Fdiv>","\u002F*\n * Shared playground design system — daily-post\n * ============================================\n * Link it from any post's playground\u002Findex.html (no per-post boilerplate):\n *\n *   \u003Clink rel=\"stylesheet\" href=\"..\u002F..\u002F..\u002Fplayground\u002Fassets\u002Fbase.css\" \u002F>\n *\n * The relative path resolves the same locally (posts\u002F\u003Cbase>\u002Fplayground\u002F) and on\n * the deployed host (public\u002Fposts\u002F\u003Cbase>\u002Fplayground\u002F), because build-site.js\n * mirrors this file to public\u002Fplayground\u002Fassets\u002Fbase.css. For a CodeSandbox\n * --embed, playground.js inlines this file so the single-file sandbox still styles.\n *\n * Then write ONLY the demo-specific CSS in your inline \u003Cstyle>. Everything below\n * — tokens, layout, panels, buttons, toggles, sliders, code blocks, status\u002Flog,\n * banners, presets — comes for free and looks consistent across every post.\n *\n * Theme-aware: dark by default, light via prefers-color-scheme AND a\n * [data-theme] override on \u003Chtml> (so a toggle can force either). Accessible:\n * real focus rings, adequate contrast, reduced-motion honored.\n *\u002F\n\n\u002F* ---------- design tokens ---------- *\u002F\n:root {\n  --bg: #0d1117;\n  --bg-grid: #ffffff0a;\n  --panel: #161b22;\n  --panel-2: #0b0e14;\n  --card: #0b0e14;\n  --ink: #e8ebf2;\n  --muted: #9aa4b2;\n  --faint: #6b7688;\n  --line: #232a35;\n  --line-soft: #ffffff12;\n  --accent: #7c9cff;\n  --accent-ink: #0b0e14;\n  --good: #3fb950;\n  --warn: #f0883e;\n  --bad: #f85149;\n  --info: #58a6ff;\n  --radius: 14px;\n  --radius-sm: 9px;\n  --shadow: 0 8px 30px #0006;\n  --shadow-sm: 0 4px 14px #0005;\n  --mono: ui-monospace, SFMono-Regular, \"SF Mono\", Menlo, Consolas, \"Liberation Mono\", monospace;\n  --sans: ui-sans-serif, system-ui, -apple-system, \"Segoe UI\", Roboto, \"Helvetica Neue\", sans-serif;\n  color-scheme: dark;\n}\n\n\u002F* Light theme — system preference, overridable by [data-theme] on \u003Chtml>. *\u002F\n@media (prefers-color-scheme: light) {\n  :root:not([data-theme=\"dark\"]) {\n    --bg: #f4f6fb;\n    --bg-grid: #00000008;\n    --panel: #ffffff;\n    --panel-2: #f0f3f9;\n    --card: #f7f9fc;\n    --ink: #131722;\n    --muted: #5b6472;\n    --faint: #8a93a3;\n    --line: #e2e7f0;\n    --line-soft: #00000010;\n    --accent: #2f6df0;\n    --accent-ink: #ffffff;\n    --good: #1a7f37;\n    --warn: #bc4c00;\n    --bad: #cf222e;\n    --info: #0969da;\n    --shadow: 0 8px 30px #0000001f;\n    --shadow-sm: 0 4px 14px #00000014;\n    color-scheme: light;\n  }\n}\n:root[data-theme=\"light\"] {\n  --bg: #f4f6fb;\n  --bg-grid: #00000008;\n  --panel: #ffffff;\n  --panel-2: #f0f3f9;\n  --card: #f7f9fc;\n  --ink: #131722;\n  --muted: #5b6472;\n  --faint: #8a93a3;\n  --line: #e2e7f0;\n  --line-soft: #00000010;\n  --accent: #2f6df0;\n  --accent-ink: #ffffff;\n  --good: #1a7f37;\n  --warn: #bc4c00;\n  --bad: #cf222e;\n  --info: #0969da;\n  --shadow: 0 8px 30px #0000001f;\n  --shadow-sm: 0 4px 14px #00000014;\n  color-scheme: light;\n}\n\n\u002F* ---------- reset & base ---------- *\u002F\n*, *::before, *::after { box-sizing: border-box; }\n\nbody {\n  margin: 0;\n  min-height: 100vh;\n  font-family: var(--sans);\n  color: var(--ink);\n  background:\n    radial-gradient(circle at 1px 1px, var(--bg-grid) 1px, transparent 0) 0 0 \u002F 24px 24px,\n    var(--bg);\n  display: flex;\n  justify-content: center;\n  align-items: flex-start;\n  padding: clamp(14px, 3vw, 26px);\n  line-height: 1.55;\n  -webkit-font-smoothing: antialiased;\n  text-rendering: optimizeLegibility;\n}\n\n\u002F* The single content column. *\u002F\n.pg {\n  width: 100%;\n  max-width: 860px;\n}\n\n\u002F* ---------- header ---------- *\u002F\n.pg-title {\n  font-size: clamp(1.15rem, 1rem + 1vw, 1.4rem);\n  font-weight: 800;\n  letter-spacing: -0.02em;\n  margin: 0 0 4px;\n  display: flex;\n  align-items: center;\n  gap: 9px;\n}\n.pg-sub {\n  color: var(--muted);\n  font-size: 0.92rem;\n  line-height: 1.5;\n  margin: 0 0 16px;\n  max-width: 66ch;\n}\n.pg-sub strong, .pg-sub b { color: var(--ink); font-weight: 700; }\n.pg-sub code { font-family: var(--mono); background: var(--line-soft); color: var(--accent);\n  padding: 1px 6px; border-radius: 6px; font-size: 0.85em; }\n\n\u002F* ---------- panels ---------- *\u002F\n.panel {\n  background: var(--panel);\n  border: 1px solid var(--line);\n  border-radius: var(--radius);\n  padding: 16px 18px;\n  margin-bottom: 14px;\n  box-shadow: var(--shadow-sm);\n}\n.panel-label {\n  font-size: 0.7rem;\n  text-transform: uppercase;\n  letter-spacing: 0.08em;\n  color: var(--muted);\n  font-weight: 800;\n  margin: 0 0 13px;\n  display: flex;\n  align-items: center;\n  gap: 8px;\n}\n.panel-label .n {\n  display: inline-grid; place-items: center;\n  width: 18px; height: 18px; border-radius: 50%;\n  background: var(--accent); color: var(--accent-ink);\n  font-size: 0.66rem; font-weight: 800;\n}\n\n\u002F* ---------- layout helpers ---------- *\u002F\n.row { display: flex; flex-wrap: wrap; gap: 12px; align-items: center; }\n.row.between { justify-content: space-between; }\n.col { display: flex; flex-direction: column; gap: 10px; }\n.grow { flex: 1 1 0; min-width: 0; }\n.wrap-controls { display: flex; flex-wrap: wrap; gap: 16px 24px; align-items: flex-end; }\n.field { display: flex; flex-direction: column; gap: 7px; min-width: 0; }\n.field > .label, .ctl-label {\n  font-size: 0.7rem; text-transform: uppercase; letter-spacing: 0.04em;\n  color: var(--muted); font-weight: 800;\n}\n\n\u002F* ---------- buttons ---------- *\u002F\n.btn {\n  font: inherit; font-weight: 650; font-size: 0.88rem;\n  cursor: pointer; user-select: none;\n  border: 1px solid var(--line);\n  background: var(--card); color: var(--ink);\n  padding: 9px 15px; border-radius: var(--radius-sm);\n  display: inline-flex; align-items: center; gap: 8px;\n  transition: background .15s ease, border-color .15s ease, transform .05s ease, color .15s ease;\n}\n.btn:hover { background: var(--line-soft); border-color: var(--muted); }\n.btn:active { transform: translateY(1px); }\n.btn:focus-visible { outline: 2px solid var(--accent); outline-offset: 2px; }\n.btn[disabled] { opacity: 0.45; cursor: not-allowed; }\n.btn.primary { background: var(--accent); border-color: var(--accent); color: var(--accent-ink); }\n.btn.primary:hover { filter: brightness(1.08); background: var(--accent); }\n.btn.good { background: var(--good); border-color: var(--good); color: #04140a; }\n.btn.bad  { background: var(--bad);  border-color: var(--bad);  color: #fff; }\n.btn.ghost { background: transparent; }\n.btn.sm { padding: 6px 11px; font-size: 0.82rem; }\n\n.btn-row { display: flex; flex-wrap: wrap; gap: 9px; }\n\n\u002F* Segmented control — a row of buttons where one is active (aria-pressed). *\u002F\n.seg { display: inline-flex; background: var(--card); border: 1px solid var(--line);\n  border-radius: var(--radius-sm); padding: 3px; gap: 3px; }\n.seg button {\n  font: inherit; font-weight: 650; font-size: 0.84rem; cursor: pointer;\n  border: none; background: transparent; color: var(--muted);\n  padding: 7px 13px; border-radius: 7px;\n  transition: background .15s ease, color .15s ease;\n}\n.seg button:hover { color: var(--ink); }\n.seg button[aria-pressed=\"true\"] { background: var(--accent); color: var(--accent-ink); }\n.seg button:focus-visible { outline: 2px solid var(--accent); outline-offset: 2px; }\n\n\u002F* Preset chips — worked-example shortcuts. *\u002F\n.presets { display: flex; flex-wrap: wrap; gap: 8px; }\n.presets .btn { background: var(--panel-2); }\n\n\u002F* ---------- toggle switch ---------- *\u002F\n.toggle { display: inline-flex; align-items: center; gap: 10px; cursor: pointer;\n  font-size: 0.88rem; font-weight: 600; user-select: none; }\n.toggle input { position: absolute; opacity: 0; width: 0; height: 0; }\n.switch { position: relative; width: 44px; height: 25px; border-radius: 999px; flex: none;\n  background: var(--line); border: 1px solid var(--line); transition: background .18s ease; }\n.switch::after { content: \"\"; position: absolute; top: 2px; left: 2px; width: 19px; height: 19px;\n  border-radius: 50%; background: #cfd6e4; transition: transform .18s ease; box-shadow: 0 1px 3px #0006; }\n.toggle input:checked + .switch { background: var(--good); border-color: var(--good); }\n.toggle input:checked + .switch::after { transform: translateX(19px); background: #fff; }\n.toggle input:focus-visible + .switch { outline: 2px solid var(--accent); outline-offset: 2px; }\n\n\u002F* ---------- range slider ---------- *\u002F\ninput[type=\"range\"] {\n  -webkit-appearance: none; appearance: none; width: 100%; height: 6px;\n  background: var(--line); border-radius: 999px; outline: none; cursor: pointer; margin: 8px 0;\n}\ninput[type=\"range\"]::-webkit-slider-thumb {\n  -webkit-appearance: none; appearance: none; width: 19px; height: 19px; border-radius: 50%;\n  background: var(--accent); border: 2px solid var(--panel); box-shadow: var(--shadow-sm); cursor: pointer;\n}\ninput[type=\"range\"]::-moz-range-thumb {\n  width: 19px; height: 19px; border-radius: 50%; background: var(--accent);\n  border: 2px solid var(--panel); box-shadow: var(--shadow-sm); cursor: pointer;\n}\ninput[type=\"range\"]:focus-visible { outline: 2px solid var(--accent); outline-offset: 3px; }\n\n\u002F* ---------- text inputs \u002F selects ---------- *\u002F\ninput[type=\"text\"], input[type=\"number\"], input[type=\"search\"], select, textarea {\n  font: inherit; color: var(--ink); background: var(--card);\n  border: 1px solid var(--line); border-radius: var(--radius-sm); padding: 8px 11px; width: 100%;\n}\ntextarea { font-family: var(--mono); font-size: 0.85rem; line-height: 1.6; resize: vertical; }\ninput:focus-visible, select:focus-visible, textarea:focus-visible {\n  outline: 2px solid var(--accent); outline-offset: 1px; border-color: var(--accent);\n}\n\n\u002F* ---------- status \u002F output \u002F log ---------- *\u002F\n.status {\n  display: flex; align-items: center; gap: 9px; flex-wrap: wrap;\n  font-size: 0.9rem; font-weight: 600;\n  padding: 11px 14px; border-radius: var(--radius-sm);\n  background: var(--panel-2); border: 1px solid var(--line); color: var(--ink);\n}\n.status.good { border-color: color-mix(in srgb, var(--good) 55%, var(--line)); }\n.status.warn { border-color: color-mix(in srgb, var(--warn) 55%, var(--line)); }\n.status.bad  { border-color: color-mix(in srgb, var(--bad) 55%, var(--line)); }\n.dot { width: 9px; height: 9px; border-radius: 50%; background: var(--muted); flex: none; }\n.dot.good { background: var(--good); } .dot.warn { background: var(--warn); }\n.dot.bad { background: var(--bad); } .dot.info { background: var(--info); }\n\n.output { background: var(--panel-2); border: 1px solid var(--line); border-radius: var(--radius-sm);\n  padding: 13px 15px; }\n.log { font-family: var(--mono); font-size: 0.8rem; line-height: 1.7; background: var(--card);\n  border: 1px solid var(--line); border-radius: var(--radius-sm); padding: 11px 14px;\n  max-height: 220px; overflow-y: auto; white-space: pre-wrap; }\n\n\u002F* ---------- code block + syntax tokens ---------- *\u002F\n.code {\n  font-family: var(--mono); font-size: 0.82rem; line-height: 1.7;\n  background: var(--panel-2); border: 1px solid var(--line); border-radius: var(--radius-sm);\n  padding: 13px 15px; overflow-x: auto; white-space: pre; tab-size: 2;\n}\n.code .tok-sel  { color: var(--accent); }\n.code .tok-prop { color: #86e29b; }\n.code .tok-kw   { color: #ff9bcb; }\n.code .tok-str  { color: #f0c674; }\n.code .tok-num  { color: #f0883e; }\n.code .tok-cmt  { color: var(--faint); font-style: italic; }\n.code .hl { background: color-mix(in srgb, var(--good) 22%, transparent); border-radius: 4px; padding: 0 3px; }\n\n\u002F* ---------- hint \u002F caption ---------- *\u002F\n.hint { font-size: 0.83rem; color: var(--muted); line-height: 1.55; margin: 10px 0 0; }\n.hint code { font-family: var(--mono); color: var(--ink); background: var(--line-soft);\n  padding: 1px 5px; border-radius: 5px; font-size: 0.86em; }\n.hint strong { color: var(--ink); }\n\n\u002F* ---------- banner (feature-support \u002F notices) ---------- *\u002F\n.banner {\n  display: none; margin-bottom: 14px; padding: 11px 14px; border-radius: 11px;\n  font-size: 0.85rem; line-height: 1.5;\n  color: var(--ink); background: color-mix(in srgb, var(--warn) 12%, var(--panel));\n  border: 1px solid color-mix(in srgb, var(--warn) 45%, var(--line));\n}\n.banner.show { display: block; }\n.banner.info { background: color-mix(in srgb, var(--info) 12%, var(--panel));\n  border-color: color-mix(in srgb, var(--info) 45%, var(--line)); }\n.banner code { font-family: var(--mono); background: var(--line-soft); padding: 1px 5px; border-radius: 5px; }\n\n\u002F* ---------- misc atoms ---------- *\u002F\n.pill { display: inline-flex; align-items: center; gap: 6px; font-size: 0.75rem; font-weight: 700;\n  padding: 3px 9px; border-radius: 999px; background: var(--line-soft); color: var(--muted); }\n.pill.good { color: var(--good); background: color-mix(in srgb, var(--good) 16%, transparent); }\n.pill.bad  { color: var(--bad);  background: color-mix(in srgb, var(--bad) 16%, transparent); }\n.mono { font-family: var(--mono); }\n.muted { color: var(--muted); }\n.big-num { font-family: var(--mono); font-size: 1.6rem; font-weight: 800; letter-spacing: -0.02em; }\n\n\u002F* Optional theme toggle button (top-right). Wire it in JS if you want it. *\u002F\n.theme-btn { position: fixed; top: 12px; right: 12px; z-index: 20; }\n\n\u002F* ---------- responsive ---------- *\u002F\n@media (max-width: 560px) {\n  .panel { padding: 14px; }\n  .wrap-controls { gap: 14px; }\n  .btn { padding: 9px 13px; }\n}\n\n\u002F* ---------- reduced motion ---------- *\u002F\n@media (prefers-reduced-motion: reduce) {\n  *, *::before, *::after { transition-duration: 0.01ms !important; animation-duration: 0.01ms !important; }\n}\n\n\n.cols { display: grid; grid-template-columns: 1fr; gap: 16px; }\n  @media (min-width: 720px) { .cols { grid-template-columns: 1fr 1fr; } }\n  .col-title { font-weight: 700; font-size: 0.95rem; margin-bottom: 8px; display: flex;\n    align-items: center; gap: 8px; }\n  .col-title .tag { font-size: 0.65rem; text-transform: uppercase; letter-spacing: 0.04em;\n    padding: 2px 7px; border-radius: 999px; border: 1px solid var(--line); color: var(--muted); }\n  #reactRoot form { display: flex; gap: 8px; align-items: center; flex-wrap: wrap; }\n  #reactRoot input { background: var(--card); border: 1px solid var(--line); border-radius: var(--radius-sm);\n    padding: 6px 9px; color: inherit; font: inherit; }\n  .boom { border: 1px dashed var(--bad); border-radius: var(--radius-sm); padding: 12px;\n    color: var(--bad); font-size: 0.85rem; }\n  .stuck { animation: none; }\n  .stuck.on { outline: 2px solid var(--bad); outline-offset: 2px; }","\"use strict\";\n  const $ = (id) => document.getElementById(id);\n  const delay = (ms) => new Promise((r) => setTimeout(r, ms));\n  const now = () => new Date().toLocaleTimeString([], { hour12: false });\n\n  function logLine(el, text) {\n    const line = document.createElement(\"div\");\n    line.textContent = `[${now()}] ${text}`;\n    el.prepend(line);\n  }\n\n  \u002F\u002F ---------- Manual (hand-rolled) panel — deliberately reproduces the bug ----------\n  let manualPending = false;\n\n  function setManualStatus(text, kind) {\n    $(\"manualStatusText\").textContent = text;\n    $(\"manualDot\").className = \"dot \" + kind;\n  }\n\n  function renderManualButton() {\n    $(\"manualSubmit\").disabled = manualPending;\n    $(\"manualSubmit\").textContent = manualPending ? \"Saving…\" : \"Save\";\n  }\n\n  $(\"manualSubmit\").addEventListener(\"click\", async () => {\n    manualPending = true;\n    renderManualButton();\n    setManualStatus(\"Saving…\", \"info\");\n    logLine($(\"manualLog\"), \"submit → isSubmitting = true\");\n    await delay(900);\n    if ($(\"failToggle\").checked) {\n      setManualStatus(\"Failed — and the button is stuck disabled. This is the bug: the catch block never reset isSubmitting.\", \"bad\");\n      logLine($(\"manualLog\"), \"request rejected → error path forgot setIsSubmitting(false)\");\n      \u002F\u002F Deliberately NOT resetting manualPending here — this is the bug from the article's hook.\n      renderManualButton();\n      return;\n    }\n    manualPending = false;\n    renderManualButton();\n    setManualStatus(\"Saved.\", \"good\");\n    logLine($(\"manualLog\"), \"request resolved → isSubmitting = false\");\n  });\n\n  $(\"resetAll\").addEventListener(\"click\", () => {\n    manualPending = false;\n    renderManualButton();\n    setManualStatus(\"Ready.\", \"info\");\n    $(\"manualLog\").innerHTML = \"\";\n    remountReact();\n  });\n\n  \u002F\u002F ---------- React panel — real React 19, real useActionState ----------\n  let remountReact = () => {};\n\n  (async () => {\n    try {\n      const React = await import(\"https:\u002F\u002Fesm.sh\u002Freact@19.2.8\");\n      const { createRoot } = await import(\"https:\u002F\u002Fesm.sh\u002Freact-dom@19.2.8\u002Fclient\");\n      const h = React.createElement;\n      $(\"cdnBanner\").classList.remove(\"show\");\n      $(\"cdnBanner\").style.display = \"none\";\n\n      const reactLog = $(\"reactLog\");\n      const log = (text) => logLine(reactLog, text);\n\n      async function saveName(prevState, formData) {\n        log(\"submit → transition starts, isPending becomes true automatically\");\n        await delay(900);\n        if ($(\"failToggle\").checked) {\n          if ($(\"throwToggle\").checked) {\n            log(\"throwing inside the action…\");\n            throw new Error(\"Simulated failure — thrown, not returned\");\n          }\n          log(\"request rejected → error RETURNED as state, isPending resets to false\");\n          return { error: \"Server said no.\" };\n        }\n        log(\"request resolved → isPending resets to false\");\n        return { error: null };\n      }\n\n      class ActionBoundary extends React.Component {\n        constructor(props) { super(props); this.state = { crashed: false }; }\n        static getDerivedStateFromError() { return { crashed: true }; }\n        componentDidCatch() { log(\"💥 nearest Error Boundary caught the throw — form unmounted, isPending is moot now\"); }\n        render() {\n          if (this.state.crashed) {\n            return h(\"div\", { className: \"boom\" },\n              \"💥 The action threw. React unmounted the form and handed control to this Error Boundary — there was no pending state to \\\"reset\\\" because the whole subtree is gone.\",\n              h(\"div\", { className: \"btn-row\", style: { marginTop: \"10px\" } },\n                h(\"button\", {\n                  className: \"btn ghost sm\",\n                  onClick: () => this.setState({ crashed: false }, this.props.onRecover),\n                }, \"Remount form\")\n              )\n            );\n          }\n          return this.props.children;\n        }\n      }\n\n      function Form() {\n        const [state, formAction, isPending] = React.useActionState(saveName, { error: null });\n        return h(\"form\", { action: formAction },\n          h(\"input\", { name: \"name\", defaultValue: \"Ada\" }),\n          h(\"button\", { className: \"btn primary\", disabled: isPending, type: \"submit\" },\n            isPending ? \"Saving…\" : \"Save\"),\n          state.error ? h(\"p\", { role: \"alert\", style: { color: \"var(--bad)\", margin: \"8px 0 0\", fontSize: \"0.85rem\" } }, state.error) : null\n        );\n      }\n\n      const root = createRoot($(\"reactRoot\"));\n      let key = 0;\n\n      function draw() {\n        root.render(h(ActionBoundary, { key: key, onRecover: () => { key++; draw(); } }, h(Form)));\n      }\n      draw();\n\n      remountReact = () => { key++; draw(); reactLog.innerHTML = \"\"; };\n    } catch (err) {\n      $(\"cdnBanner\").textContent =\n        \"Couldn't load React from esm.sh (CDN blocked or offline). The manual panel on the left still demonstrates the bug without it.\";\n    }\n  })();",{"height":11,"autorun":12},520,true,{"slug":4,"title":14,"excerpt":15,"coverUrl":16,"vertical":17},"React Form Actions: useActionState & useFormStatus Guide","How React 19 form Actions manage pending state automatically — useActionState, useFormStatus, and useOptimistic explained with the bug they replace.","\u002Fmedia\u002Fcovers\u002Freact-weekly-form-actions-pending-state.png",{"slug":18},"dev",[20,34,46],{"id":21,"slug":18,"name":22,"tagline":23,"description":24,"accentFrom":25,"accentTo":26,"icon":27,"defaultLocale":28,"locales":29,"features":31,"position":33},"019fe637-3d33-714b-b57f-23e163ffca0c","Web Development","Read it. Run it. Prove it.","A post a day on modern web development — most with an editable playground and a quiz that explains every answer. Free, no account needed.","violet-500","cyan-400","◇","en",[28,30],"fa",{"courses":12,"paths":12,"articles":12,"exams":32,"flashcards":32,"packages":12,"community":12,"certificates":12,"teams":12,"commerce":12},false,0,{"id":35,"slug":36,"name":37,"tagline":38,"description":39,"accentFrom":40,"accentTo":25,"icon":41,"defaultLocale":28,"locales":42,"features":44,"position":45},"019fe637-3dc2-754c-8657-0f175bfee7c6","lang","Languages","Learn a language the way you learn a codebase.","Grammar explained the way good documentation explains an API — one idea at a time, each with a quiz.","amber-400","⌘",[28,30,43],"es",{"courses":32,"paths":32,"articles":12,"exams":32,"flashcards":12,"packages":32,"community":12,"certificates":12,"teams":32,"commerce":32},2,{"id":47,"slug":48,"name":49,"tagline":50,"description":51,"accentFrom":52,"accentTo":53,"icon":54,"defaultLocale":28,"locales":55,"features":56,"position":57},"7b3c16f2-931d-410e-802e-e1fa4edab7de","soft","Soft Skills","The half of the job nobody wrote documentation for.","Weekly, on the parts of working life that decide more than your code does — first weeks, meetings, interviews, promotions, and the people around you. Written from what actually happens, and recorded as a podcast you can listen to on the walk.","emerald-400","teal-300","◉",[28],{"courses":32,"paths":32,"articles":12,"exams":32,"flashcards":32,"packages":32,"community":12,"certificates":32,"teams":32,"commerce":32},3,[59,63,67,71,75,79,83,86,90,94,98,102],{"slug":60,"name":61,"articles":62},"webdev","Webdev",90,{"slug":64,"name":65,"articles":66},"javascript","Javascript",74,{"slug":68,"name":69,"articles":70},"frontend","Frontend",69,{"slug":72,"name":73,"articles":74},"css","Css",31,{"slug":76,"name":77,"articles":78},"tutorial","Tutorial",20,{"slug":80,"name":81,"articles":82},"typescript","Typescript",12,{"slug":84,"name":85,"articles":82},"performance","Performance",{"slug":87,"name":88,"articles":89},"react","React",11,{"slug":91,"name":92,"articles":93},"browser","Browser",7,{"slug":95,"name":96,"articles":97},"grammar","Grammar",6,{"slug":99,"name":100,"articles":101},"html","Html",5,{"slug":103,"name":104,"articles":101},"programming","Programming"]