v2.0.1

Update NPM to have latest README and github links since move to rackt.

v2.0.0

Breaking Changes

createSelector, createStructuredSelector, and custom selector creators check argument types

Input selectors are now verified to be functions during selector creation. If verification fails an error is thrown, allowing for a useful stack trace. (see #49)

There is a small chance that this could cause a breakage in existing code that contains a faulty selector that is never called.

v1.1.0

New features

createStructuredSelector

createStructuredSelector is a convenience function that helps with a common pattern when using Reselect. The selector passed to a connect decorator often just takes other selectors and maps them to keys in an object:

const mySelectorA = state => state.a;
const mySelectorB = state => state.b;

const structuredSelector = createSelector(
   mySelectorA,
   mySelectorB,
   mySelectorC,
   (a, b, c) => ({
     a, 
     b,
     c
   })
);

createStructuredSelector takes an object whose properties are input-selectors and returns a structured selector. The structured selector returns an object with the same keys as the inputSelectors argument, but with the selectors replaced with their values.

const mySelectorA = state => state.a;
const mySelectorB = state => state.b;

const structuredSelector = createStructuredSelector({
  x: mySelectorA,
  y: mySelectorB
});

const result = structuredSelector({a: 1, b: 2}); // will produce {x: 1, y: 2}

v1.0.0

Breaking Changes

If upgrading from 0.0.2, see the release notes for v1.0.0-alpha

v1.0.0-alpha2

New features

/src directory included in npm package
js:next field added to package.json

v1.0.0-alpha

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);