--- slug: 80-cookbook title: Cookbook description: Copy-paste Synsema patterns — input validation with partial results, plus pointers to the full patterns (HTTP API, CRUD, LLM op, agent tools, secrets). example_ids: [cookbook] --- # Cookbook Copy-paste patterns. Each is complete and doctested elsewhere — start here, then follow the link. ## Validate input, keep partial results Validate a payload into a typed value; sum the valid ones and skip the bad ones with `try/recover`: ```synsema -- Doc cookbook: validate a payload into a typed value, and sum valid ones with -- partial results (try/recover skips the bad ones). A copy-paste-ready pattern. intent: "doc cookbook: validate + partial results" type Order id: number total: number task validate_order(payload) when not contains(payload, "total") raise("missing total") when (payload["total"]) < 0 raise("total must be >= 0") give Order(payload["id"], payload["total"]) task bad_order() give validate_order({"id": 2, "total": 0 - 5}) task safe_total(payloads) let total be 0 each p in payloads try let o be validate_order(p) set total to total + (total of o) recover err log "skipped: " + err -- partial results: skip the invalid ones give total print("safe_total of mixed orders → " + text(safe_total([{"id": 1, "total": 10}, {"id": 2, "total": 0 - 1}, {"id": 3, "total": 5}]))) test "validate accepts good input and rejects bad" assert_eq(total of validate_order({"id": 1, "total": 100}), 100) assert_error(bad_order) test "partial results: invalid orders are skipped" assert_eq(safe_total([{"id": 1, "total": 10}, {"id": 2, "total": 0 - 1}, {"id": 3, "total": 5}]), 15) ``` ## The other patterns (each fully shown on its page) - **A styled page from a layout + components** — `{ layout }`, named slots, `{ include … with {props} }`, inline CSS in a `{ raw }` block → **[Build a website](/en/0.6.x/41a-build-a-website)**. - **A classic form (no JS)** — `