1

私は以前に尋ねたこの質問から得たこのコーヒースクリプトを持っています。

window.getObject = (theObject, key, val) ->
  result = null
  if theObject instanceof Array
    i = 0
    while i < theObject.length
      result = getObject(theObject[i], key, val)
      i++
  else
    for prop of theObject
      return theObject  if theObject[prop] is val  if prop is key
      result = getObject(theObject[prop], key, val)  if theObject[prop] instanceof Object or theObject[prop] instanceof Array
  result

ここで結果が見つかります：

return theObject  if theObject[prop] is val  if prop is key

ここで、再帰を停止して結果を返す必要があります。しかし、それはループから抜け出さないため、結果をnullagianに設定します。確かに私は愚かな何かを逃しています！

編集

今私はこれがうまくいくと思うように変更しました

window.getObject = (theObject, key, val) ->
  result = null
  if theObject instanceof Array
    i = 0
    while i < theObject.length
      result = getObject(theObject[i], key, val)
      i++
  else
    for prop of theObject
      if theObject[prop] is val and prop is key
        result = theObject 
        console.log "I found it"
        break
      console.log "I must not log after found it was logged"
      result = getObject(theObject[prop], key, val)  if theObject[prop] instanceof Object or theObject[prop] instanceof Array
    console.log "stop!!"
  result

ログは次の順序で表示されます。

I must not log after found it was logged ui.js:49
I must not log after found it was logged ui.js:49
I must not log after found it was logged ui.js:49
stop!! ui.js:54
stop!! ui.js:54
I must not log after found it was logged ui.js:49
I must not log after found it was logged ui.js:49
I must not log after found it was logged ui.js:49
I found it ui.js:46
stop!! ui.js:54
I must not log after found it was logged ui.js:49
I must not log after found it was logged ui.js:49
I must not log after found it was logged ui.js:49
stop!! ui.js:54
stop!! ui.js:54
stop!! ui.js:54
stop!! ui.js:54
I must not log after found it was logged ui.js:49
stop!! ui.js:54
I must not log after found it was logged ui.js:49
stop!! ui.js:54
stop!! ui.js:54
stop!!
4

2 に答える 2

1

ログは正しく、再帰呼び出しを示しています。

 I must not log after found it was logged ui.js:49
     I must not log after found it was logged ui.js:49
         I must not log after found it was logged ui.js:49
             stop!! ui.js:54
         stop!! ui.js:54
     I must not log after found it was logged ui.js:49
         I must not log after found it was logged ui.js:49
             I must not log after found it was logged ui.js:49
                 I found it ui.js:46
                stop!! ui.js:54
             I must not log after found it was logged ui.js:49
                 I must not log after found it was logged ui.js:49
                     I must not log after found it was logged ui.js:49
                    stop!! ui.js:54
                stop!! ui.js:54
            stop!! ui.js:54
        stop!! ui.js:54
     I must not log after found it was logged ui.js:49
        stop!! ui.js:54
     I must not log after found it was logged ui.js:49
        stop!! ui.js:54
    stop!! ui.js:54
stop!!

（配列部分を無視すると、「ログに記録してはならない」たびに​​別の再帰レベルが呼び出され、各呼び出しは「stopp」で終了します）

ご覧のとおり、「見つけた」後、ループはすぐに停止します。

しかし、それはループから抜け出さないため、結果をnullagianに設定します

それは次に高いレベルで起こります。あなたは喜んで割り当てていますがresult = getObject(…)、ここでは再帰呼び出しが何かをもたらした場合でも壊れていません（配列ループでも同じです）。

ただし、result変数を維持する代わりに、アーリーリターンが読みやすくなっています（必要ありませんbreak）。

window.getObject = (theObject, key, val) ->
  if theObject instanceof Array
    for item in theObject
      result = getObject(item, key, val)
      return result  if result
  else
    for prop, item of theObject
      return theObject  if item is val and prop is key
      result = getObject(item, key, val)  if item instanceof Object or item instanceof Array
      return result  if result
  null
于 2013-03-22T11:01:34.423 に答える
0

結果がnullでない場合は、もう1回ブレークする必要があるようです。このようなもの：

result = getObject(theObject[prop], key, val)  if theObject[prop] instanceof Object or theObject[prop] instanceof Array
break if result not null

この関数の再帰呼び出し内でオブジェクトが見つかった場合は、ループを中断する必要があります。

于 2013-03-22T11:01:02.657 に答える