Source: https://tanstack.com/query/v5/docs/framework/angular/reference/interfaces/basequerynarrowing

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Menu

• Home

• Frameworks

• Contributors

• Community Resources

• GitHub

• Discord

Getting Started

• Overview
  
  angular

• Installation
  
  angular

• Quick Start
  
  angular

• Angular HttpClient and other data fetching clients
  
  angular

• Devtools
  
  angular

• TypeScript
  
  angular

• Zoneless
  
  angular

Guides & Concepts

• Important Defaults
  
  angular

• Queries
  
  angular

• Query Keys
  
  angular

• Query Functions
  
  angular

• Query Options
  
  angular

• Network Mode
  
  angular

• Parallel Queries
  
  angular

• Dependent Queries
  
  angular

• Background Fetching Indicators
  
  angular

• Window Focus Refetching
  
  angular

• Disabling/Pausing Queries
  
  angular

• Query Retries
  
  angular

• Paginated Queries
  
  angular

• Infinite Queries
  
  angular

• Initial Query Data
  
  angular

• Placeholder Query Data
  
  angular

• Mutations
  
  angular

• Mutation Options
  
  angular

• Query Invalidation
  
  angular

• Invalidation from Mutations
  
  angular

• Optimistic Updates
  
  angular

• Query Cancellation
  
  angular

• Scroll Restoration
  
  angular

• Filters
  
  angular

• Caching
  
  angular

• Default Query Fn
  
  angular

• Testing
  
  angular

• Does this replace state managers?
  
  angular

API Reference

• QueryClient
  
  core

• QueryCache
  
  core

• MutationCache
  
  core

• QueryObserver
  
  core

• InfiniteQueryObserver
  
  core

• QueriesObserver
  
  core

• streamedQuery
  
  core

• focusManager
  
  core

• onlineManager
  
  core

• notifyManager
  
  core

• timeoutManager
  
  core

• Angular Reference
  
  angular

• Functions / injectQuery
  
  angular

• Functions / injectMutation
  
  angular

ESLint

• ESLint Plugin Query
  
  core

• Exhaustive Deps
  
  core

• Stable Query Client
  
  core

• No Rest Destructuring
  
  core

• No Unstable Deps
  
  core

• Infinite Query Property Order
  
  core

Examples

• Simple
  
  angular

• Basic
  
  angular

• Auto Refetching / Polling / Realtime
  
  angular

• Optimistic Updates
  
  angular

• Pagination
  
  angular

• Infinite query with maxPages
  
  angular

• Angular Router
  
  angular

• RxJS autocomplete
  
  angular

• Query options from a service
  
  angular

• Devtools embedded panel
  
  angular

On this page

• Interface: BaseQueryNarrowing<TData, TError>

• Type Parameters

• Properties

• isError()

• Parameters

• this

• Returns

• isPending()

• Parameters

• this

• Returns

• isSuccess()

• Parameters

• this

• Returns

BaseQueryNarrowing

Copy Markdown

Interface: BaseQueryNarrowing<TData, TError>
============================================

Defined in: types.ts:57

Type Parameters
---------------

• TData = unknown

• TError = DefaultError

Properties
---------- ### isError()

ts

isError: (this) => this is CreateBaseQueryResult<TData, TError, CreateStatusBasedQueryResult<"error", TData, TError>>;


isError: (this) => this is CreateBaseQueryResult<TData, TError, CreateStatusBasedQueryResult<"error", TData, TError>>;

Defined in: types.ts:65

#### Parameters ##### this

CreateBaseQueryResult <TData, TError>

#### Returns

this is CreateBaseQueryResult<TData, TError, CreateStatusBasedQueryResult<"error", TData, TError>>

---

### isPending()

ts

isPending: (this) => this is CreateBaseQueryResult<TData, TError, CreateStatusBasedQueryResult<"pending", TData, TError>>;


isPending: (this) => this is CreateBaseQueryResult<TData, TError, CreateStatusBasedQueryResult<"pending", TData, TError>>;

Defined in: types.ts:72

#### Parameters ##### this

CreateBaseQueryResult <TData, TError>

#### Returns

this is CreateBaseQueryResult<TData, TError, CreateStatusBasedQueryResult<"pending", TData, TError>>

---

### isSuccess()

ts

isSuccess: (this) => this is CreateBaseQueryResult<TData, TError, CreateStatusBasedQueryResult<"success", TData, TError>>;


isSuccess: (this) => this is CreateBaseQueryResult<TData, TError, CreateStatusBasedQueryResult<"success", TData, TError>>;

Defined in: types.ts:58

#### Parameters ##### this

CreateBaseQueryResult <TData, TError>

#### Returns

this is CreateBaseQueryResult<TData, TError, CreateStatusBasedQueryResult<"success", TData, TError>>

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