Class Query<Q>

constructor

• new Query<Q>(params?: Q): Query<Q>

  Type Parameters

  • Q

  Parameters

  • Optionalparams: Q

  Returns Query<Q>

Optional Readonlyparams

Readonlytype

ap

• ap<A, B, QVal>(_resourceWithValue: Resource<A, QVal>): Resource<B, QVal>

  Applies a function wrapped in a Resource to the Data value, supporting applicative functor operations. For Data, applies the function if the input is Data; otherwise, returns unchanged.

  Type Parameters

  • A
  • B
  • QVal

  Parameters

  • _resourceWithValue: Resource<A, QVal>

  Returns Resource<B, QVal>

  A new Resource with the applied result or the original non-Data/Failure state.

  Example

  const fnRes = Resource.Data((x: number) => x + 1, { id: '123' });
  const dataRes = Resource.Data(42, { id: '123' });
  const result = fnRes.ap(dataRes); // Data<43, { id: '123' }>
  
  const failureFn = Resource.Failure<(x: number) => number>(['fn error']);
  const result2 = failureFn.ap(dataRes); // Failure<number> (propagates failure from function resource)
  
  const failureVal = Resource.Failure<number>(['val error']);
  const result3 = fnRes.ap(failureVal); // Failure<number> (propagates failure from value resource)
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chain

• chain<R, P>(_fn: (x: Data<any, Q>) => Resource<R, P>): Resource<R, P>

  Chains a function that returns a Resource, enabling monadic composition. For Data, applies the function; for others, returns unchanged.

  Type Parameters

  • R
  • P

  Parameters

  • _fn: (x: Data<any, Q>) => Resource<R, P>

  Returns Resource<R, P>

  The Resource returned by fn (for Data) or the same instance (for others).

  Example

  const data = Resource.Data(42, { id: '123' });
  const result = data.chain(d => Resource.Data(d.value * 2, d.params)); // Data<84, { id: '123' }>
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getDataOr

• getDataOr(value: any): any

  Returns the Data value or a fallback value for non-Data states.

  Parameters

  • value: any

    Fallback value for non-Data states.

  Returns any

  The Data value or the fallback.

  Example

  const data = Resource.Data(42);
  const value = data.getDataOr(0); // 42
  const failure = Resource.Failure(['error']);
  const fallback = failure.getDataOr(0); // 0
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map

• map<R>(_fn: (x: any) => R): Query<Q>

  Transforms the Data value using a function, preserving the Resource structure. Acts as a functor operation, similar to Array.map. Non-Data variants return unchanged.

  Type Parameters

  • R

  Parameters

  • _fn: (x: any) => R

  Returns Query<Q>

  A new Resource with the transformed value (for Data) or the same instance (for others).

  Example

  const data = Resource.Data(42, { id: '123' });
  const result = data.map(x => x + 1); // Data<43, { id: '123' }>
  Copy

mapSafe

• mapSafe<R>(_fn: (x: any) => R): Query<Q>

  Safely transforms the Data value, catching errors and returning Failure if the function throws. Useful for error-prone operations (e.g., parsing JSON).

  Type Parameters

  • R

  Parameters

  • _fn: (x: any) => R

  Returns Query<Q>

  A new Data with the transformed value or Failure if an error occurs.

  Example

  const data = Resource.Data('{"name": "Jane"}', { id: '123' });
  const result = data.mapSafe(JSON.parse); // Data<{ name: 'Jane' }> or Failure
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matchWith

• matchWith<R>(pattern: ResourcePattern<any, Q, R>): R

  Matches the Resource state with a pattern, returning a value. Enables declarative state handling, similar to a switch statement.

  Type Parameters

  • R

  Parameters

  • pattern: ResourcePattern<any, Q, R>

    Object with functions for each Resource state.

  Returns R

  The result of the matching function.

  Example

  const resource = Resource.Data(42, { id: '123' });
  const result = resource.matchWith({
    Data: ({ value }) => value * 2,
    Query: () => 0,
    Empty: () => 0,
    Failure: () => 0,
  }); // 84
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matchWithPartial

• matchWithPartial(pattern: Partial<ResourcePattern<any, Q, void>>): void

  Matches the Resource state with a partial pattern, performing side effects.

  Parameters

  • pattern: Partial<ResourcePattern<any, Q, void>>

    Partial object with functions for some Resource states.

  Returns void

  Example

  Resource.Failure(['error']).matchWithPartial({
    Failure: ({ messages }) => console.log(messages),
  });
  Copy

of

• of<R>(value: R): Data<R, Q>

  Lifts a value into a Data Resource, preserving existing params (if any). Acts as the monadic pure operation.

  Type Parameters

  • R

  Parameters

  • value: R

    Value to lift into Data.

  Returns Data<R, Q>

  A new Data Resource with the value and existing params.

  Example

  const data = Resource.Data(42, { id: '123' });
  const result = data.of(100); // Data<100, { id: '123' }>
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update

• update<P>(params: P): Query<P>

  Transitions to a Query state with new parameters.

  Type Parameters

  • P

  Parameters

  • params: P

    New parameters for the Query.

  Returns Query<P>

  A new Query Resource.

  Example

  const data = Resource.Data(42, { id: '123' });
  const query = data.update({ id: '456' }); // Query<{ id: '456' }>
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Staticof

• of<Q>(params?: Q): Query<Q>

  Creates a new Query Resource.

  Type Parameters

  • Q

  Parameters

  • Optionalparams: Q

    Optional parameters (e.g., query params).

  Returns Query<Q>