Manifold Countdown

\n setInput(e.target.value)}\n />\n {\n try {\n const u = new URL(input);\n const slug = u.pathname.split(\"/\").filter(Boolean).pop();\n if (slug) window.location.href = `/${slug}`;\n } catch {}\n }}\n >\n Show Countdown\n \n \n Try example: Gemini 3 Pro Release Date\n \n

\n );\n}\n\nexport default async function server(req: Request): Promise {\n const url = new URL(req.url);\n const path = url.pathname.slice(1);\n const isSlug = path && !path.startsWith(\"http\");\n\n if (!isSlug) {\n return homepage();\n }\n\n const slug = path.split(\"/\").filter(Boolean).pop()?.split(\"?\")[0] ?? \"\";\n const res = await fetch(`https://manifold.markets/api/v0/slug/${slug}`);\n if (!res.ok) return new Response(\"Market not found\", { status: 404 });\n const contract = await res.json();\n\n if (!Array.isArray(contract.answers) || contract.answers.length === 0)\n return new Response(\"This market has no answers (not a date market)\", { status: 400 });\n\n const expected = getExpectedDate(contract);\n const formatted = formatExpectedDate(expected, contract);\n const title = `${contract.question} by ${contract.creatorName}`;\n\n return new Response(`\n\n \n \n ${title}\n \n \n \n

${title}

COUNTDOWN

${formatted}

\n View Source\n

\n \n`, {\n headers: { \"content-type\": \"text/html; charset=utf-8\" }\n });\n}\n\nfunction homepage() {\n return new Response(`\n\n \n \n Manifold Countdown\n \n \n \n \n \n

\n \n`, {\n headers: { \"content-type\": \"text/html; charset=utf-8\" }\n });\n}\n\nfunction getExpectedDate(contract) {\n const { answers, shouldAnswersSumToOne, isResolved } = contract;\n const probs = answers.map((a) => isResolved ? a.prob : getAnswerProbability(contract, a.id)).filter((x) => x != null);\n const mids = answers.map((a) => a.midpoint);\n\n if (shouldAnswersSumToOne) {\n return probs.reduce((sum, p, i) => sum + p * mids[i], 0);\n } else {\n const discrete = [probs[0]];\n for (let i = 1; i < probs.length; i++) discrete.push(probs[i] - probs[i - 1]);\n const afterLast = 1 - probs[probs.length - 1];\n\n let total = 0;\n for (let i = 0; i < probs.length; i++) total += mids[i] * discrete[i];\n if (afterLast > 0 && mids.length > 1) {\n const last = mids[mids.length - 1];\n const secondLast = mids[mids.length - 2];\n const period = last - secondLast;\n total += (last + period) * afterLast;\n }\n return total;\n }\n}\n\nfunction formatExpectedDate(value, contract) {\n const { answers } = contract;\n const mids = answers.map((a) => a.midpoint);\n const min = Math.min(...mids);\n const max = Math.max(...mids);\n if (isNaN(value) || min === max) return \"N/A\";\n\n const manyYears = max - min > 10 * 365 * 24 * 60 * 60 * 1000;\n const formatter = new Intl.DateTimeFormat(\"en-US\", manyYears ? { year: \"numeric\" } : { year: \"numeric\", month: \"long\", day: \"numeric\" });\n return formatter.format(value);\n}\n\nfunction getAnswerProbability(contract, answerId) {\n return contract.answers.find((a) => a.id === answerId)?.prob;\n}","deleted","label",[98],"permalink","https://www.val.town/x/dcm31/countdown_date_market/code/main.tsx","extension","actionData","errors"]