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use-deep-compare-effect
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It's React's useEffect hook, except using deep comparison on the inputs, not reference equality
WARNING: Please only use this if you really can't find a way to use
React.useEffect
. There's often a better way to do what you're trying to do than a deep comparison.
React's built-in useEffect
hook has a second argument called
the "dependencies array" and it allows you to optimize when React will call your
effect callback. React will do a comparison between each of the values (via
Object.is
) to determine whether your effect callback should be
called.
The problem is that if you need to provide an object for one of those dependencies and that object is new every render, then even if none of the properties changed, your effect will get called anyway.
This module is distributed via npm which is bundled with node and should be installed as one of your project's dependencies:
npm install --save use-deep-compare-effect
You use it in place of React.useEffect
.
NOTE: Only use this if your values are objects or arrays that contain objects. Otherwise, you should just use
React.useEffect
. In case of "polymorphic" values (eg: sometimes object, sometimes a boolean), useuseDeepCompareEffectNoCheck
, but do it at your own risk, as maybe there can be better approaches to the problem.
NOTE: Be careful when your dependency is an object which contains function. If that function is defined on the object during a render, then it's changed and the effect callback will be called every render. Issue has more context.
Example:
import React from 'react'
import ReactDOM from 'react-dom'
import useDeepCompareEffect from 'use-deep-compare-effect'
function Query({query, variables}) {
// some code...
useDeepCompareEffect(
() => {
// make an HTTP request or whatever with the query and variables
// optionally return a cleanup function if necessary
},
// query is a string, but variables is an object. With the way Query is used
// in the example above, `variables` will be a new object every render.
// useDeepCompareEffect will do a deep comparison and your callback is only
// run when the variables object actually has changes.
[query, variables],
)
return <div>{/* awesome UI here */}</div>
}
Looking to contribute? Look for the Good First Issue label.
Please file an issue for bugs, missing documentation, or unexpected behavior.
Please file an issue to suggest new features. Vote on feature requests by adding a 👍. This helps maintainers prioritize what to work on.
Thanks goes to these people (emoji key):
This project follows the all-contributors specification. Contributions of any kind welcome!
MIT
FAQs
It's react's useEffect hook, except using deep comparison on the inputs, not reference equality
The npm package use-deep-compare-effect receives a total of 563,811 weekly downloads. As such, use-deep-compare-effect popularity was classified as popular.
We found that use-deep-compare-effect demonstrated a not healthy version release cadence and project activity because the last version was released a year ago. It has 1 open source maintainer collaborating on the project.
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Research
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