preserve line breaks javascript

perserve_linebreaks.js

var perserve_linebreaks = function(text) {
    var html = text.replace(/\r\n\r\n/g, "</p><p>"),
        html = html.replace(/\r\n/g, "<br />"),
        html = html.replace(/\n\n/g, "</p><p>"),
        html = html.replace(/\n/g, "<br />"),
        html = "<p>"+html+"</p>";  
    return html
};