Add Create A Schema That Matches On Any Object as a Zod TIL

zod/create-a-schema-that-matches-on-any-object.md

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+# Create A Schema That Matches On Any Object
+
+Typically when creating an object schema with Zod, you have to specify the keys
+and their types that make up the object.
+
+```typescript
+import {z} from 'zod'
+
+const objectSchema = z.object({ id: z.string() })
+
+const obj = objectSchema.parse({ id: 1, type: 'user' })
+//=> { id: 1 }
+
+objectSchema.parse({ _id: 1, _type: 'user' })
+//=> ZodError
+```
+
+If, however, you want a generic object schema that is ostensibly only checking
+that the thing is an object and then allows any and all key-value pairs, you
+can use the [`passthrough()`](https://github.com/colinhacks/zod#passthrough)
+function.
+
+```typescript
+import {z} from 'zod'
+
+const anyObjectSchema = z.object({}).passthrough()
+
+const obj = anyObjectSchema.parse({ id: 1, type: 'user' })
+//=> { id: 1, type: 'user' }
+```