Convert a string to regular expression ruby

I need to convert string like "/[\w\s]+/" to regular expression.

"/[\w\s]+/" => /[\w\s]+/

I tried using different Regexp methods like:

Regexp.new("/[\w\s]+/") => /\/[w ]+\//, similarly Regexp.compile and Regexp.escape. But none of them returns as I expected.

Further more I tried removing backslashes:

Regexp.new("[\w\s]+") => /[w ]+/ But not have a luck.

Then I tried to do it simple:

str = "[\w\s]+"
=> "[w ]+"

It escapes. Now how could string remains as it is and convert to a regexp object?

Looks like here you need the initial string to be in single quotes (refer this page)

>> str = '[\w\s]+'
 => "[\\w\\s]+" 
>> Regexp.new str
 => /[\w\s]+/

To be clear

  /#{Regexp.quote(your_string_variable)}/

is working too

edit: wrapped your_string_variable in Regexp.quote, for correctness.

This method will safely escape all characters with special meaning:

/#{Regexp.quote(your_string)}/

For example, . will be escaped, since it's otherwise interpreted as 'any character'.

Remember to use a single-quoted string unless you want regular string interpolation to kick in, where backslash has a special meaning.

Using % notation:

%r{\w+}m => /\w+/m

regex_string = '\W+'
%r[#{regex_string}]

From help:

%r[ ] Interpolated Regexp (flags can appear after the closing delimiter)

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