I have a problem with Freemarker. I want to remove all the special characters from text string in freemarker: "!"#$%&'()*+,-./:;<=>?#[]^_`{|}~". I tried writing regular expression for this but it is not working and facing some errors:
<#assign s = 'Foo bAr$%,*^%#()":& baar'>
${s?replace('["!"#$%&'()*+,-./\:;<=>?#[]^_`{|}~"]', '', 'r')}
Please help
You could simplify this solution like this unless there are other special characters you explicitely want to keep:
${s?replace("[^\\w]|_", "", "r")}
I was able to remove these special characters after going through:
Freemarker escape regex characters
I have used below expression to make it work.
replace('[$%,*#():&"^!{}|~<>=""+-./;?_'`#\[\]\\ ]', '', 'r')
Related
That is what I have, and I tried to split like:
(Using Golang)
idPost = strings.Split(idPost,'"')
but the compiler said IncompatibleAssign using '"'.
Use a back quote instead of an apostrophe, example:
idPost = strings.Split(idPost,`"`)
you need to escape it, so your question is how to escape characters in go.
Escapes and multiline strings
You will find this is similar across many languages:
dPost = strings.Split(idPost,"\"")
So I want to split a string in java on any non-alphanumeric characters.
Currently I have been doing it like this
words= Str.split("\\W+");
However I want to keep apostrophes("'") in there. Is there any regular expression to preserve apostrophes but kick the rest of the junk? Thanks.
words = Str.split("[^\\w']+");
Just add it to the character class. \W is equivalent to [^\w], which you can then add ' to.
Do note, however, that \w also actually includes underscores. If you want to split on underscores as well, you should be using [^a-zA-Z0-9'] instead.
For basic English characters, use
words = Str.split("[^a-zA-Z0-9']+");
If you want to include English words with special characters (such as fiancé) or for languages that use non-English characters, go with
words = Str.split("[^\\p{L}0-9']+");
I want to extract #hashtags from a string, also those that have special characters such as #1+1.
Currently I'm using:
#hashtags ||= string.scan(/#\w+/)
But it doesn't work with those special characters. Also, I want it to be UTF-8 compatible.
How do I do this?
EDIT:
If the last character is a special character it should be removed, such as #hashtag, #hashtag. #hashtag! #hashtag? etc...
Also, the hash sign at the beginning should be removed.
The Solution
You probably want something like:
'#hash+tag'.encode('UTF-8').scan /\b(?<=#)[^#[:punct:]]+\b/
=> ["hash+tag"]
Note that the zero-width assertion at the beginning is required to avoid capturing the pound sign as part of the match.
References
String#encode
Ruby's POSIX Character Classes
This should work:
#hashtags = str.scan(/#([[:graph:]]*[[:alnum:]])/).flatten
Or if you don't want your hashtag to start with a special character:
#hashtags = str.scan(/#((?:[[:alnum:]][[:graph:]]*)?[[:alnum:]])/).flatten
How about this:
#hashtags ||=string.match(/(#[[:alpha:]]+)|#[\d\+-]+\d+/).to_s[1..-1]
Takes cares of #alphabets or #2323+2323 #2323-2323 #2323+65656-67676
Also removes # at beginning
Or if you want it in array form:
#hashtags ||=string.scan(/#[[:alpha:]]+|#[\d\+-]+\d+/).collect{|x| x[1..-1]}
Wow, this took so long but I still don't understand why scan(/#[[:alpha:]]+|#[\d\+-]+\d+/) works but not scan(/(#[[:alpha:]]+)|#[\d\+-]+\d+/) in my computer. The difference being the () on the 2nd scan statement. This has no effect as it should be when I use with match method.
I have this string:
"some text\nandsomemore"
I need to remove the "\n" from it. I've tried
"some text\nandsomemore".gsub('\n','')
but it doesn't work. How do I do it? Thanks for reading.
You need to use "\n" not '\n' in your gsub. The different quote marks behave differently.
Double quotes " allow character expansion and expression interpolation ie. they let you use escaped control chars like \n to represent their true value, in this case, newline, and allow the use of #{expression} so you can weave variables and, well, pretty much any ruby expression you like into the text.
While on the other hand, single quotes ' treat the string literally, so there's no expansion, replacement, interpolation or what have you.
In this particular case, it's better to use either the .delete or .tr String method to delete the newlines.
See here for more info
If you want or don't mind having all the leading and trailing whitespace from your string removed you can use the strip method.
" hello ".strip #=> "hello"
"\tgoodbye\r\n".strip #=> "goodbye"
as mentioned here.
edit The original title for this question was different. My answer is for the original question.
When you want to remove a string, rather than replace it you can use String#delete (or its mutator equivalent String#delete!), e.g.:
x = "foo\nfoo"
x.delete!("\n")
x now equals "foofoo"
In this specific case String#delete is more readable than gsub since you are not actually replacing the string with anything.
You don't need a regex for this. Use tr:
"some text\nandsomemore".tr("\n","")
use chomp or strip functions from Ruby:
"abcd\n".chomp => "abcd"
"abcd\n".strip => "abcd"
I am using nokogiri to screen scrape some HTML. In some occurrences, I am getting some weird characters back, I have tracked down the ASCII code for these characters with the following code:
#parser.leads[0].phone_numbers[0].each_byte do |c|
puts "char=#{c}"
end
The characters in question have an ASCII code of 194 and 160.
I want to somehow strip these characters out while parsing.
I have tried the following code but it does not work.
#parser.leads[0].phone_numbers[0].gsub(/160.chr/,'').gsub(/194.chr/,'')
Can anyone tell me how to achieve this?
I found this question while trying to strip out invisible characters when "trimming" a string.
s.strip did not work for me and I found that the invisible character had the ord number 194
None of the methods above worked for me but then I found "Convert non-breaking spaces to spaces in Ruby " question which says:
Use /\u00a0/ to match non-breaking spaces: s.gsub(/\u00a0/, ' ') converts all non-breaking spaces to regular spaces
Use /[[:space:]]/ to match all whitespace, including Unicode whitespace like non-breaking spaces. This is unlike /\s/, which matches only ASCII whitespace.
So glad I found that! Now I'm using:
s.gsub(/[[:space:]]/,'')
This doesn't answer the question of how to gsub specific character codes, but if you're just trying to remove whitespace it seems to work pretty well.
Your problem is that you want to do a method call but instead you're creating a Regexp. You're searching and replacing strings consisting of the string "160" followed by any character and then the string "chr", and then doing the same except with "160" replaced with "194".
Instead, do gsub(160.chr, '').
Update (2018): This code does not work in current Ruby versions. Please refer to other answers.
You can also try
s.gsub(/\xA0|\xC2/, '')
or
s.delete 160.chr+194.chr
First thought would be should you be using gsub! instead of gsub
gsub returns a string and gsub! performs the substitution in place
I was getting "invalid multibyte escape" error while trying the above solution, but for a different situation. Google was return \xA0 when the number is greater than 999 and I wanted to remove it. So what I did was use return_value.gsub(/[\xA0]/n,"") instead and it worked perfectly fine for me.