作者uranusjr (←這人是超級笨蛋)
看板Python
標題Re: [問題] 關於list的append方法
時間Wed Jul 19 02:51:36 2017
※ 引述《LessonWang (橘白Cat)》之銘言：
1F：→ zerof: pass by reference. 07/18 13:53
2F：→ uranusjr: 跟 C 沒有關係吧, 也不是 pass by reference 不要亂教.. 07/18 15:44
4F：→ uranusjr: @zerof: By reference 和 by value 的差異不是這樣看的 07/18 21:10
5F：→ uranusjr: 這個議題去 Google 就有一堆資料, 可以試著研究看看 07/18 21:12
6F：→ s860134: 我記得書上是說根據傳入參數 mutable/immutable 來分 07/19 02:03
7F：→ s860134: 當然你說最底層的實做是用 C 一定是指標只來只去拉... 07/19 02:04
8F：→ zerof: 認知就是 by ref, 你要不要貼個參考資料說它不是? 07/19 02:06
9F：→ s860134: stackoverflow 986006 也是討論得亂七八糟XD 07/19 02:21
啊你的認知就是錯的啊, 我就說 Google 就有一堆資料了你都沒有在聽嘛
https://www.google.com.tw/?q=python+call+by+reference
就看前五個結果好不好
1.
https://stackoverflow.com/questions/986006
這個上面也有提到, 直接看 accepted answer (同時也是分數最高)
Arguments are passed by assignment. [...] the parameter passed in is
actually a reference to an object (but the reference is passed by value).
2.
https://stackoverflow.com/questions/13299427
[...] while you can't explicitly pass variables by reference in Python [...]
3.
http://d.pr/KbZ2AS
Is Python call-by-value or call-by-reference? Neither.
4.
http://www.python-course.eu/passing_arguments.php
The authors who call the mechanism call-by-value and those who call it
call-by-reference are stretching the definitions until they fit. Correctly
speaking, Python uses a mechanism, which is known as "Call-by-Object",
sometimes also called "Call by Object Reference" or "Call by Sharing".
5.
http://d.pr/GpSU86
Unfortunately, Python is "pass-by-object-reference", of which it is
often said:
"Object references are passed by value."
好啦反正眾說紛紜大家都在發明自己的名詞
但是上面好像是有個共通點就是所有人都一致同意 call/pass by reference 是錯的
大guy4這樣
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作者 Linux (Windows) 看板 C_and_CPP
標題 [問題] 如何確認是否 free 對記憶體
時間 Fri Nov 2 00:14:03 2012
11F：→ akasan:valgrind, 但 windowns 版的沒試過XD 11/02 00:43
12F：→ akasan:linux 上那真的是不二選擇了 11/02 00:44
13F：→ Linux:我是用 Windows ....>"< 11/02 00:45
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※ 文章網址: https://webptt.com/m.aspx?n=bbs/Python/M.1500403904.A.E95.html
※ 編輯: uranusjr (218.161.19.12), 07/19/2017 02:52:09
14F：推 brightwish: python宣告變數其實是把物件參照(變數名稱)指向物件名 07/19 07:24
15F：→ brightwish: 稱(值) 所以是呼叫物件參照 07/19 07:24
16F：推 LessonWang: 真的眾說紛紜 ... 07/19 08:26
17F：推 Yshuan: 開發角度上 預設變數都是ref來去預防side effect為佳 07/19 16:36
18F：→ Yshuan: 任何assinment都要有心理預期 上保險不會虧 07/19 16:38