Retain comment when TypeScript compiles -

look @ code in typescript playground. need comments placed in result js code have ability determine browser ie according this question. cc_on ie conditional compilation directive.

typescript

window.isbrowser = {     ie: function() {         return /*@cc_on!@*/false;     } }; 

compiled javascript

window.isbrowser = {     ie: function () {         return false;     } }; 

if use webessentials 2012, have option retain comments. after installing extension, in vs 2012, go tools > options > web essentials > typescript > keep comments , set value true.

your sample works fine me in vs2012 we:

window["isbrowser"] = {  // presume came plugin or script? window doesn't have 'isbrowser' property.     ie: function () {         return /*@cc_on!@*/false;     } }; 

compiles to:

window["isbrowser"] = {     ie: function () {         return /*@cc_on!@*/ false;     } }; 

update: although recommend webessentials kinds of other reasons, can without - see @stevefenton's useful comment below.