在bash脚本中，除问号和感叹号外，使用perl将句点替换为替代

Question

最初我想出了如何删除所有文件的句号，然后再添加它们:

 Remove periods at end of titles
 perl -pi -e 's/title = {(.*).},/title = {$1},/g' $1
 # Add periods back so all files are the same (comment out if no periods wanted)
 perl -pi -e 's/title = {(.*)},/title = {$1.},/g' $1

理想情况下，我想做的是检查每个标题是否有句号，感叹号或问号，如果没有，然后添加句号。我认为有一种简单的方法来做这个替换，但我不太了解语法。

例如输入:

title = This has a period.
title = This has nothing
title = This has a exclamation!
title = This has a question?

输出将是:

title = This has a period.
title = This has nothing.
title = This has a exclamation!
title = This has a question?

所以它只会在没有任何标记的情况下才会将行修改为句号

Answer 1

KISS，使用否定字符类

perl -pi -e 's/title = {(.*[^.?!])},/title = {$1.},/g' $1

演示

或

使用消极的目光。

perl -pi -e 's/title = {(.*)(?<![.?!])},/title = {$1.},/g' $1

演示

Answer 2

您可以使用此sed:

sed '/^title = .*[.!?]$/!s/$/./' file

(或)

sed '/^title = .*[^.!?]$/s/$/./' file

测试:

$ sed '/^title = .*[.!?]$/!s/$/./' file
title = This has a period.
title = This has nothing.
title = This has a exclamation!
title = This has a question?