My Vim replace with a regex is throwing a `E488: Trailing characters`

Question

I'm trying to find all instances of a Twitter handle, and wrap an anchor tag around them.

:%s/\(@[\w]\)/<a href="http://www.twitter.com/\1">\1<\/a>/gc 

Which gives me:

E488: Trailing characters 

Answer 1

When the separator character (/ in your case) between {pattern} and {string} is contained in one of those, it must be escaped with a \. A trick to avoid that is to use a different separator character, e.g. #:

:%s#@\(\w\+\)#<a href="http://www.twitter.com/\1">\0</a>#gc 

PS: If it should do what I think it should do, your pattern is wrong; see my correction.

Answer 2

If you have this when replacing within a selected block of text, it may be because you mistakenly typed %s when you should only type s

I had this happen by selecting a block, typing : and at the prompt :'<,'>, typing %s/something/other/ resulting in :'<,'>%s/something/other/ when the proper syntax is :'<,'>s/something/other/ without the percent.