---
url: /unthrown/api/pothos/index-1.md
---
[**@unthrown/pothos**](index.md)

***

[@unthrown/pothos](index.md) / index

# index

## Type Aliases

### Caseable

```ts
type Caseable = 
  | {
  _tag: string;
}
  | {
  code: string;
};
```

Defined in: [refusals.ts:31](https://github.com/btravstack/unthrown/blob/653a65764fd8d9eb399f952fe479dddd365bc3da/packages/pothos/src/refusals.ts#L31)

A failure that names its case: a string `_tag`, or a string `code`. A field's
resolver (and `outcomeOf`) answers `Failure & Caseable`, so a failure with a
member naming no case does not compile — no refusal could answer it.

***

### CaseOf

```ts
type CaseOf<Failure> = Failure extends object ? Tag : Failure extends object ? 
  | "_tag" extends keyof Failure ? string extends Failure["_tag"] ? string : Extract<Failure["_tag"], string> : never
  | Code : never;
```

Defined in: [refusals.ts:14](https://github.com/btravstack/unthrown/blob/653a65764fd8d9eb399f952fe479dddd365bc3da/packages/pothos/src/refusals.ts#L14)

The name of a failure's case: its `_tag` (a `TaggedError`), else its `code`
(an `ORPCError`, or any `code`-discriminated object). An optional string
`_tag` beside a `code` names the case whenever it is present, so both count;
a tag that may hold any string (`unknown`, `string`) makes the cases
non-finite, which `Refusals` refuses.

#### Type Parameters

| Type Parameter |
| ------ |
| `Failure` |

***

### Refusals

```ts
type Refusals<Failure> = [Failure] extends [never] ? object : [CaseOf<Failure>] extends [never] ? { readonly [Case in CaseOf<Failure>]: never } : [NonFiniteOf<CaseOf<Failure>>] extends [never] ? { readonly [Case in CaseOf<Failure>]: (failure: FailureOf<Failure, Case>) => Error } : object;
```

Defined in: [refusals.ts:65](https://github.com/btravstack/unthrown/blob/653a65764fd8d9eb399f952fe479dddd365bc3da/packages/pothos/src/refusals.ts#L65)

One GraphQL error class per case of `Failure`, each constructed from the
failure of that case. It is exhaustive by construction: a missing case, an
extra one, or a class built from another case's failure does not compile —
the same guarantee the error combinators' matcher gives, keyed by the case
the failure names. A resolver that cannot fail takes an empty record, and a
failure whose cases cannot be enumerated takes none at all.

The extra-case check is TypeScript's excess-property check, which holds for
an object literal: write the record inline, or declare it apart with
`satisfies Refusals<Failure>`.

The classes are the field's error types for `@pothos/plugin-errors`, so each
must be registered as an object type (`builder.objectType(NotFoundError, …)`).

#### Type Parameters

| Type Parameter |
| ------ |
| `Failure` |

***

### ResolvedShape

```ts
type ResolvedShape<Type, Shape> = Type extends 
  | readonly unknown[]
  | {
  kind: "List";
} ? Shape extends readonly infer Item[] ? Iterable<Item | Promise<Item>> & object : Shape : Shape;
```

Defined in: [index.ts:56](https://github.com/btravstack/unthrown/blob/653a65764fd8d9eb399f952fe479dddd365bc3da/packages/pothos/src/index.ts#L56)

A field's value as its `Ok` may carry it. A GraphQL list (`[Type]`, a
`ListRef`) takes any synchronous iterable of its items, each possibly a
promise — an array, a generator, never a string; any other field takes its
shape as it is, an array-shaped scalar included. An `Ok` holding an `Error`
is answered as a defect at runtime: the errors plugin would take it for a
refusal.

#### Type Parameters

| Type Parameter |
| ------ |
| `Type` |
| `Shape` |

***

### ResultFieldOptions

```ts
type ResultFieldOptions<Types, ParentShape, Type, Nullable, Args, Kind, Failure> = Omit<FieldOptionsFromKind<Types, ParentShape, Type, Nullable, Args, Kind, ParentShape, unknown>, "resolve" | "errors"> & object;
```

Defined in: [index.ts:85](https://github.com/btravstack/unthrown/blob/653a65764fd8d9eb399f952fe479dddd365bc3da/packages/pothos/src/index.ts#L85)

`t.field`'s options with a `Result`-answering `resolve` and the `refusals`
its failure maps to. `errors` keeps `@pothos/plugin-errors`' other options
(`directResult`, `dataField`, …); its `types` are the refusals'.

#### Type Declaration

| Name | Type | Defined in |
| ------ | ------ | ------ |
| `errors?` | `Omit`<`ErrorFieldOptions`<`Types`, `Type`, [`ResolvedShape`](#resolvedshape)<`Type`, `ShapeFromTypeParam`<`Types`, `Type`, `false`>>, `Nullable`>, `"types"`> | [index.ts:97](https://github.com/btravstack/unthrown/blob/653a65764fd8d9eb399f952fe479dddd365bc3da/packages/pothos/src/index.ts#L97) |
| `refusals` | `NoInfer`<[`Refusals`](#refusals)<`Failure`>> | [index.ts:108](https://github.com/btravstack/unthrown/blob/653a65764fd8d9eb399f952fe479dddd365bc3da/packages/pothos/src/index.ts#L108) |
| `resolve` | [`ResultResolver`](#resultresolver)<`Types`, `ParentShape`, `Args`, [`ResolvedShape`](#resolvedshape)<`Type`, `ShapeFromTypeParam`<`Types`, `Type`, `Nullable`>>, `Failure`> | [index.ts:109](https://github.com/btravstack/unthrown/blob/653a65764fd8d9eb399f952fe479dddd365bc3da/packages/pothos/src/index.ts#L109) |

#### Type Parameters

| Type Parameter |
| ------ |
| `Types` *extends* `SchemaTypes` |
| `ParentShape` |
| `Type` *extends* `TypeParam`<`Types`> |
| `Nullable` *extends* `FieldNullability`<`Type`> |
| `Args` *extends* `InputFieldMap` |
| `Kind` *extends* `FieldKind` |
| `Failure` |

***

### ResultResolver

```ts
type ResultResolver<Types, Parent, Args, Value, Failure> = (parent, args, context, info) => 
  | Result<Value, Failure & Caseable>
  | AsyncResult<Value, Failure & Caseable>;
```

Defined in: [index.ts:67](https://github.com/btravstack/unthrown/blob/653a65764fd8d9eb399f952fe479dddd365bc3da/packages/pothos/src/index.ts#L67)

A resolver answering a `Result`: Pothos' four resolver arguments, the
field's value as the `Ok` and `Failure` as the error channel. Every member
of `Failure` must name its case (`Caseable`).

#### Type Parameters

| Type Parameter |
| ------ |
| `Types` *extends* `SchemaTypes` |
| `Parent` |
| `Args` *extends* `InputFieldMap` |
| `Value` |
| `Failure` |

#### Parameters

| Parameter | Type |
| ------ | ------ |
| `parent` | `Parent` |
| `args` | `InputShapeFromFields`<`Args`> |
| `context` | `Types`\[`"Context"`] |
| `info` | `GraphQLResolveInfo` |

#### Returns

| `Result`<`Value`, `Failure` & [`Caseable`](#caseable)>
| `AsyncResult`<`Value`, `Failure` & [`Caseable`](#caseable)>

## Variables

### default

```ts
const default: "unthrown" = "unthrown";
```

Defined in: [index.ts:155](https://github.com/btravstack/unthrown/blob/653a65764fd8d9eb399f952fe479dddd365bc3da/packages/pothos/src/index.ts#L155)

## Functions

### outcomeOf()

```ts
function outcomeOf<Value, Failure>(
   result, 
   refusals, 
   defaultTypes?
): Promise<Value | Error>;
```

Defined in: [refusals.ts:178](https://github.com/btravstack/unthrown/blob/653a65764fd8d9eb399f952fe479dddd365bc3da/packages/pothos/src/refusals.ts#L178)

A `Result` as a DataLoader answers one key: the value, or the refusal its
failure maps to. A `Defect` is returned as an `Error`, never thrown, so one
key's bug does not reject the batch — wrapped (`new Error("Defect", { cause })`)
when one of the field's refusals or the builder's `defaultTypes` would claim
it. Pass the builder's `defaultTypes`: a loader can only reject a key with an
`Error`, so a base `Error` among them claims every defect a loader reports.

#### Type Parameters

| Type Parameter |
| ------ |
| `Value` |
| `Failure` |

#### Parameters

| Parameter | Type | Default value |
| ------ | ------ | ------ |
| `result` | | `Result`<`Value`, Failure & Caseable> | `AsyncResult`<`Value`, Failure & Caseable> | `undefined` |
| `refusals` | [`Refusals`](#refusals)<`Failure`> | `undefined` |
| `defaultTypes` | readonly `ErrorClass`\[] | `[]` |

#### Returns

`Promise`<`Value` | `Error`>