Backslashes - Regular Expression - Javascript

I wanted to build a JS function concatting a list of arguments to a valid path (since I could not be sure whether a part of the path is given with or without slashes)

This is the function:

concatPath = function() {
    var path = "";
    for(var i = 0; i < arguments.length; i++)   {
        path += arguments[i].replace("(\\|/)$|^(\\|/)", "") + "/";
    }
    return path;
}

The used RegEx matched all beginning and ending slashes and backslashes on http://regexpal.com But the function does not work properly (RegEx does not match). Furthermore, Chrome states

SyntaxError: Invalid regular expression: /(\)$|^(\)/: Unterminated group

when I just use the RegEx

 (\\)$|^(\\)

However, using the RegEx

 (\\)$|^(\\)

works fine.

Is it too late or did I missed something special?

Thanks in advance!

Leo