Python展開製表符長度計算

Question

當我使用expandtabs時，如何計算字符串的長度，我感到困惑。我認爲expandtabs會用適當數量的空格替換標籤（默認每個標籤的空格數爲8）。但是，當我使用不同長度的字符串和不同數量的選項卡運行命令時，長度計算與我認爲的不同（即，每個選項卡並不總是導致每個實例的字符串長度增加8 「/ t」）。

下面是一個詳細的腳本輸出和註釋，解釋了我認爲應該是上面執行的命令的結果。請有人解釋當使用展開標籤時如何計算長度？

IDLE 2.6.5  
>>> s = '\t' 
>>> print len(s) 
1 
>>> #the length of the string without expandtabs was one (1 tab counted as a single space), as expected. 
>>> print len(s.expandtabs()) 
8 
>>> #the length of the string with expandtabs was eight (1 tab counted as eight spaces). 
>>> s = '\t\t' 
>>> print len(s) 
2 
>>> #the length of the string without expandtabs was 2 (2 tabs, each counted as a single space). 
>>> print len(s.expandtabs()) 
16 
>>> #the length of the string with expandtabs was 16 (2 tabs counted as 8 spaces each). 
>>> s = 'abc\tabc' 
>>> print len(s) 
7 
>>> #the length of the string without expandtabs was seven (6 characters and 1 tab counted as a single space). 
>>> print len(s.expandtabs()) 
11 
>>> #the length of the string with expandtabs was NOT 14 (6 characters and one 8 space tabs). 
>>> s = 'abc\tabc\tabc' 
>>> print len(s) 
11 
>>> #the length of the string without expandtabs was 11 (9 characters and 2 tabs counted as a single space). 
>>> print len(s.expandtabs()) 
19 
>>> #the length of the string with expandtabs was NOT 25 (9 characters and two 8 space tabs). 
>>> 

Answer 1

就像當你在一個文本編輯器輸入標籤，製表符增加長度的8

所以接下來的倍數：

• '\t'本身是8，明顯。
• '\t\t'是在3個字符16
• 'abc\tabc'開始，然後一個標籤將其推到8，然後將最後'abc'從8至11將其推...
• 'abc\tabc\tabc'同樣開始於3，選項卡凸塊它至圖8，另一個'abc'前進到11，則另一個選項卡它推至16，和最終'abc'帶來的長度至19

Answer 2

翼片遞增列指針的8的倍數：

>>> 'abc\tabc'.expandtabs().replace(' ', '*') 
'abc*****abc'