查找以“+”结尾的行 [英] Find lines that end with "+"

问题描述

我无法形成一个grep正则表达式，它只能找到那些以+符号结尾的行。例如：

应该匹配 - 这是一个示例行+

不应该匹配 - 这是或之间的另一个+，这是另一个+，介于+

解决方案

使用 $ 来指示line：

  grep'+ $'file 
  

示例

  $ cat a 
这是一个示例行+ 
这是在
 hello 
 
 $ grep'+ $'a 
之间的另一个+这是一个示例行+ 
  

更新

如果我想显示行最终只有+。即使
线是这样的这是一个在bw +最后+的线。

然后您可以使用 awk
不希望匹配此行。 / code>：

  awk'/ \ + $ /&& split（$ 0，a，\ +）== 2'文件
  





说明

• / \ + $ / 匹配以 + 。


• split（$ 0，a，\ +）== 2 基于 + 分隔符的块。返回值是件数，所以 2 表示它只包含一个 + 。





示例





  $ cat a 
这是一个示例行+ 
这是在
之间的另一个+你好+和+ 
你好
 
 $ awk'/ \ + $ /&& amp ; split（$ 0，a，\ +）== 2'a 
这是一个示例行+ 
  




I am unable to form a grep regex which will find me only those lines that end with + signs. Example:

Should match - This is a sample line +

Should not match - This is another with + in between or This is another with + in between and ends with +

解决方案

Do use $ to indicate the end of the line:

grep '+$' file

Example

$ cat a
This is a sample line +
This is another with + in between
hello

$ grep '+$' a
This is a sample line +

Update

What if I want to display lines which only has + in the end. Even if a line is like this This is a line with + in bw and in the end +. I don't want this line to be matched.

Then you can use awk:

awk '/\+$/ && split($0, a, "\+")==2' file

Explanation

• /\+$/ matches lines ending with +.
• split($0, a, "\+")==2 divides the string in blocks based on the + delimiter. The return value is the number of pieces, so 2 means that it just contains one +.

Example

$ cat a
This is a sample line +
This is another with + in between
Hello + and +
hello

$ awk '/\+$/ && split($0, a, "\+")==2' a
This is a sample line +

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