ahooks-v2/lib/usePrevious/index.js

react hooks library

"use strict";

Object.defineProperty(exports, "__esModule", {
  value: true
});

var react_1 = require("react");

function usePrevious(state, compare) {
  var prevRef = react_1.useRef();
  var curRef = react_1.useRef();
  var needUpdate = typeof compare === 'function' ? compare(curRef.current, state) : true;

  if (needUpdate) {
    prevRef.current = curRef.current;
    curRef.current = state;
  }

  return prevRef.current;
}

exports["default"] = usePrevious;