正则表达式：删除以字符开头和结尾的单词或字母

Question

我想使用Regex删除R中以特定字符开头和结尾的单词或字母。

例如

"I want to delete @word&"

应该是

 "I want to delete"

和

"I  want to delete @p&"

应该是

"I want to delete" 

Answer 1

您可以使用gsub：

gsub("@[^&]*&","","I want to delete @word&")
# [1] "I want to delete "


gsub("(^|\\s)@[^&]*&","","I  want to delete @p&")
# [1] "I  want to delete "

处理多余空间的方式将取决于您的实际情况，但我认为，如果可以接受调整后的输出，则以下内容应该可以：

trimws(gsub("\\s*@[^&]*&","","@nope& hello @nope& world @nope&"))
# [1] "hello world"

Answer 2

不同的模式-仅使+不贪心：

gsub("@.+?&","","I want to delete @word&")