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import {equals} from './equals'
const NO_MATCH_FOUND = Symbol ? Symbol('NO_MATCH_FOUND') : undefined
const getMatchingKeyValuePair = (cases, testValue, defaultValue) => {  let iterationValue
  for (let index = 0; index < cases.length; index++) {    iterationValue = cases[index].test(testValue)
    if (iterationValue !== NO_MATCH_FOUND) {      return iterationValue    }  }
  return defaultValue}
const isEqual = (testValue, matchValue) => {  const willReturn =    typeof testValue === 'function'      ? testValue(matchValue)      : equals(testValue, matchValue)
  return willReturn}
const is = (testValue, matchResult = true) => ({  key: testValue,  test: matchValue =>    isEqual(testValue, matchValue) ? matchResult : NO_MATCH_FOUND,})
class Switchem {  constructor(defaultValue, cases, willMatch) {    if (cases === undefined && willMatch === undefined) {      this.cases = []      this.defaultValue = undefined      this.willMatch = defaultValue    } else {      this.cases = cases      this.defaultValue = defaultValue      this.willMatch = willMatch    }
    return this  }
  default(defaultValue) {    const holder = new Switchem(defaultValue, this.cases, this.willMatch)
    return holder.match(this.willMatch)  }
  is(testValue, matchResult) {    return new Switchem(      this.defaultValue,      [...this.cases, is(testValue, matchResult)],      this.willMatch    )  }
  match(matchValue) {    return getMatchingKeyValuePair(this.cases, matchValue, this.defaultValue)  }}
export function switcher(input) {  return new Switchem(input)}