@antmjs/vantui/lib/wxs/memoize.js

一套适用于Taro3及React的vantui组件库

"use strict";

var _interopRequireDefault = require("@babel/runtime/helpers/interopRequireDefault");
Object.defineProperty(exports, "__esModule", {
  value: true
});
exports.memoize = memoize;
var _typeof2 = _interopRequireDefault(require("@babel/runtime/helpers/typeof"));
/**
 * Simple memoize
 * wxs doesn't support fn.apply, so this memoize only support up to 2 args
 */
/* eslint-disable */

function isPrimitive(value) {
  var type = (0, _typeof2.default)(value);
  return type === 'boolean' || type === 'number' || type === 'string' || type === 'undefined' || value === null;
}

// mock simple fn.call in wxs
function call(fn, args) {
  if (args.length === 2) {
    return fn(args[0], args[1]);
  }
  if (args.length === 1) {
    return fn(args[0]);
  }
  return fn();
}
function serializer(args) {
  if (args.length === 1 && isPrimitive(args[0])) {
    return args[0];
  }
  var obj = {};
  for (var i = 0; i < args.length; i++) {
    obj['key' + i] = args[i];
  }
  return JSON.stringify(obj);
}
function memoize(fn) {
  var cache = {};
  return function () {
    var key = serializer(arguments);
    if (cache[key] === undefined) {
      cache[key] = call(fn, arguments);
    }
    return cache[key];
  };
}