reselect - npm Package Versions

v1.0.0-alpha - 2015/09/01

Breaking Changes

createSelectorCreator takes a user specified memoize function instead of a custom valueEqualsFunc.

Before

import { isEqual } from 'lodash'
import { createSelectorCreator } from 'reselect'

const deepEqualsSelectorCreator = createSelectorCreator(isEqual)

After

import { isEqual } from 'lodash'
import { createSelectorCreator, defaultMemoize } from 'reselect'

const deepEqualsSelectorCreator = createSelectorCreator(defaultMemoize, isEqual)

New features

Variadic Dependencies

Selector creators can receive a variadic number of dependencies as well as an array of dependencies.

Before

const selector = createSelector(
  [state => state.a, state => state.b],
  (a, b) => a * b
)

After

const selector = createSelector(
  state => state.a,
  state => state.b,
  (a, b) => a * b
)

Access ownProps in Selector

Selector dependencies can receive a variadic number of parameters allowing a selector to receive ownProps passed from mapToProps in connect.

const selector = createSelector(
  state => state.a,
  (state, props) => state.b * props.c,
  (_, props) => props.d,
  (a, bc, d) => a + bc + d
)

Configurable Memoize Function

import { createSelectorCreator } from 'reselect'
import memoize from 'lodash.memoize'

let called = 0
const customSelectorCreator = createSelectorCreator(memoize, JSON.stringify)
const selector = customSelectorCreator(
  state => state.a,
  state => state.b,
  (a, b) => {
    called++
    return a + b
  }
)
assert.equal(selector({ a: 1, b: 2 }), 3)
assert.equal(selector({ a: 1, b: 2 }), 3)
assert.equal(called, 1)
assert.equal(selector({ a: 2, b: 3 }), 5)
assert.equal(called, 2)