PropTypes in reaction + redux

Question

in redux examples, I see something like this:

Footer.propTypes = {
  completedCount: PropTypes.number.isRequired,
  activeCount: PropTypes.number.isRequired,
  filter: PropTypes.string.isRequired,
  onClearCompleted: PropTypes.func.isRequired,
  onShow: PropTypes.func.isRequired
}

So what do these PropTypes really do? Are they enjoyable or must-have?

thank

Answer 1

As finalFreq pointed out, I am correcting! "The above example will work fine in future response versions. It will respond to obsolescence by calling the proptypes function directly, but annotating the component will work very well in current and future versions."

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FlowType: https://flowtype.org/docs/getting-started.html#_

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: , proptypes .

Answer 2

propTypes , . , , , , .

.isRequired, , , . , , , .

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