Slice

Info

Slices are central to managing your app's state. They bundle together actions, state fields, derived fields, and effects for cleaner and efficient state management.

To create a slice:

import { createKey } from '@nalanda/core';
 
const key = createKey('<slice-name>', [
    // dependencies
]);
 
export const yourSlice= key.slice({
    // fields
    // actions
});

Also read Key or Slice guide.

.name

The name of the slice.

Example:

slice.name // 'counter'

.get()

Gets the exposed field values in a given StoreState.

Signature:

slice.get(storeState: StoreState): { [name: fieldName]: value }

Arguments:

• storeState - The store state to get value from

.getField()

Gets the value of an exposed field.

Signature:

slice.getField(storeState: StoreState, fieldName: string): value

Arguments:

• storeState - The store state to get value from
• fieldName - The name of the exposed field to get value from

Example:

const slice = key.slice({
    counter: counterField
})
slice.getField(storeState, 'counter') // 0

.track()

Tracks the value of exposed fields by returning an object.

This only works inside an effect.

Signature:

slice.track(store: EffectStore): ValueObject

Arguments:

• store - the store passed by the effect callback

.trackField()

Tracks the value of an exposed field.

This only works inside an effect.

Signature:

slice.trackField(store: EffectStore, fieldName: string): value

Arguments:

• store - the store passed by the effect callback
• fieldName - The name of the exposed field to track value from

Example:

const slice = key.slice({
    counter: counterField
})
 
const counter = slice.trackField(storeState, 'counter');