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import { equals } from './equals.js'
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)}