javascript Invalid regular expression with token '\'

Question

i created the following regex for finding a url matching a word in the complete path and that does't contain the point character.

(\path\?*)([^.]*)$

It works on https://www.regex101.com/#javascript, but on grunt in the connect task when i define this connect task:

middleware: function(connect, options) {
 var middlewares = [];

 middlewares.push(modRewrite(["(\path\?*)([^.]*)$ /home.html [L]"])); 
    options.base.forEach(function(base) {
      middlewares.push(connect.static(base));
    });
    return middlewares;
  }

i got this error: Invalid regular expression: /(home?*)([^.]*)$/: Nothing to repeat and the IDE warn me in the two slash (\path\ ) between the 'path ' word.

Why i can use those slashes? What can i use to replace those slashes? Thanks very much

`"(\\path\\?*)([^.]*)$ /home.html [L]"` – Avinash Raj Jan 19 '15 at 14:53 — Avinash Raj, Jan 19 '15 at 14:53

score 2 · Accepted Answer · answered Jan 19 '15 at 15:03

2

The \ is a special character in javascript so you need to escape it, if you intend to use it. You can escape it by adding another \. ex: \\

answered Jan 19 '15 at 15:03

Travis Pettry

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score 0 · Answer 2 · answered Jan 19 '15 at 15:09

Backslash belongs to "Javascript special characters"

Because you use backslashes inside a double quoted string, you have to write each one twice to tell the parser that you actually want to ouput a backslah. This is mandatory inside double quoted and single quoted strings.

You might browse the documentation .. for instance MDN documentation

Then search for "JavaScript special characters"

javascript Invalid regular expression with token '\'

2 Answers2