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addReducer helper causes components to re-render unnecessarily

See original GitHub issue


Thank you for this great library, it really shorten the code.

I have noticed that my components using render whenever global is updated, even if it updates something not used by this component. Is it normal ? I was expecting a behavior like React.PureComponent, the component just renders when the part of the state he uses get rendered, is it possible ?

Especially in my case, I have a component that uses a reducer function, it doesn’t use a value of the state. I am not on react 16.7 so I cannot use useGlobal.

PS: I am on react 16.6.

Thank you

Issue Analytics

  • State:closed
  • Created 5 years ago
  • Comments:5 (3 by maintainers)

github_iconTop GitHub Comments

CharlesStovercommented, Nov 21, 2018

Thank you for reporting this. I’ve pinpointed the bug, and I’ll deploy 0.1.1 sometime today to resolve it.

CharlesStovercommented, Nov 21, 2018

Thanks for providing an example. What version of ReactN are you using? 0.0.9 or 0.1.0?

EDIT: This does look to be a bug with the addReducer helper.

You can see that it does not occur with the setGlobal method:

class Button extends React.Component {

  incrementX = () => {
    this.setGlobal(state => ({
      x: state.x + 1

  render() {
    console.log('render button');
    return (
      <button onClick={this.incrementX}>

I’ll look into getting this fixed for the addReducer helper as well.

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