I used chomp to remove multiple "\n" from a string, but it only removes one. How can I remove multiple "\n" characters from a string?
My string looks like:
"Ttyyuhhhjhhhh\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n"
-
I see you are rather new to Stackoverflow (incidentally, so am I). Remember that after asking a question, once/if you receive an answer that truly answers your question, is a good idea to approve it. @gargvipanPablo Fernandez heelhook– Pablo Fernandez heelhook2012-11-17 05:10:33 +00:00Commented Nov 17, 2012 at 5:10
Add a comment
|
4 Answers
The method strip will take care of removing all leading and trailing white spaces for you.
If you only want to remove the \n from the end of the string you can use a regexp such as:
string.gsub!(/(\n*)$/, '')
or rstrip!
string.rstrip!
answered Nov 16, 2012 at 14:23
Pablo Fernandez heelhook
12.7k3 gold badges23 silver badges20 bronze badges
7 Comments
DigitalRoss
Well, "...leading and trailing white space...".
Pablo Fernandez heelhook
You are right, I always thought of white space as referring to only horizontal space, but I see now that vertical is also included in the definition. Thanks. Edited.
the Tin Man
(\n*) is needlessly complex. There is no need to group \n, nor do you care about the case where there is no new-line so use \n by itself: sub(/\n+$/, '') is all that's needed.
Kamil Šrot
@theTinMan IMO is the whole use of regular expression needlessly complex, why not to use
*strip methods to actually strip the string?Pablo Fernandez heelhook
Both ways are presented in this answer, regular expressions and
strip. |
As you need to strip from the end of your string, use rstrip
str = "Ttyyuhhhjhhhh\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n"
str.rstrip()
Comments
If you really just want to remove newlines, and not other whitespace, strip and rstrip (which remove all whitespace) are not the answer. The regex /\n+\Z/ will match any number of newlines at the end of a string:
str1 = "text \t\n\n\n"
# => "text \t\n\n\n"
str1.sub(/\n+\Z/, '')
# => "text \t"
Note that this works (and without the multiline regexp modifier /m) on multi-line strings as well, leaving newlines in the middle of the string intact:
str2 = str1 + str1 + str1
# => "text \t\n\n\ntext \t\n\n\ntext \t\n\n\n"
str2.sub(/\n+\Z/, '')
# => "text \t\n\n\ntext \t\n\n\ntext \t"
Comments
"Ttyyuhhhjhhhh\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n".gsub(/\n$/,'')
1 Comment
the Tin Man
The regex is wrong.
/$\n/ would find new-lines after the current line, not new-lines at the end of the current line. Instead, you need /\n$/.