为什么小写[i]在可视块模式下不起作用？

Question

我经常忘记如何以视觉块模式插入并再次阅读答案Shift+i.

正如洪河.吴在评论中不知所措:

为什么小写i在视觉模式下不起作用？

技术原因是什么？

Answer 1

因为i并且a在所有视觉模式中不像正常模式那样行为的原因是i并且a用于将选择扩展到文本对象.正如您所见:help visual-operators:

4. Operating on the Visual area

The operators that can be used are:
    ~   switch case                 
    d   delete                      
    c   change (4)                  
    y   yank                        
    >   shift right (4)                 
    <   shift left (4)                  
    !   filter through external command (1)     
    =   filter through 'equalprg' option command (1)    
    gq  format lines to 'textwidth' length (1)      

The objects that can be used are:
    aw  a word (with white space)           
    iw  inner word                  
    aW  a WORD (with white space)           
    iW  inner WORD                  
    as  a sentence (with white space)           
    is  inner sentence                  
    ap  a paragraph (with white space)          
    ip  inner paragraph                 
    ab  a () block (with parenthesis)           
    ib  inner () block                  
    aB  a {} block (with braces)            
    iB  inner {} block                  
    at  a <tag> </tag> block (with tags)        
    it  inner <tag> </tag> block            
    a<  a <> block (with <>)                
    i<  inner <> block                  
    a[  a [] block (with [])                
    i[  inner [] block                  
    a"  a double quoted string (with quotes)        
    i"  inner double quoted string          
    a'  a single quoted string (with quotes)        
    i'  inner simple quoted string          
    a`  a string in backticks (with backticks)      
    i`  inner string in backticks           

Additionally the following commands can be used:
    :   start Ex command for highlighted lines (1)  
    r   change (4)                  
    s   change                      
    C   change (2)(4)                   
    S   change (2)                  
    R   change (2)                  
    x   delete                      
    D   delete (3)                  
    X   delete (2)                  
    Y   yank (2)                    
    p   put                     
    J   join (1)                    
    U   make uppercase                  
    u   make lowercase                  
    ^]  find tag                    
    I   block insert                    
    A   block append                    

因此,只需在可视块模式下使用block insert大写I或block append大写A命令即可.

Answer 2

该命令在光标位置之前i插入。在可视块模式下，光标位置（通常）代表所选内容的右下角，并且光标位置包含在块中。

因此， 的语义i不匹配，这就是为什么它被排除在 Vim 实现之外（添加它可能只是对源代码进行简单的一行更改）。语义确实匹配I（在任何文本之前插入）和（在任何文本之后A插入），这就是它们在可视块模式下可用的原因。