How to find in a script existence of a specific value from enumeration list attribute

target-type.literal.l11 , target-type.literal.l8 and a few more literals.

I need to find out if one of the 'existing' values is id "target-type.literal.l11" (this literal name is "Other") .

What is the way to "search" for a specific value in a list attribute?

Current (not working :-( ) script:

/*******************************************************************************/
dojo.provide("com.MTD_OtherTargetType");
dojo.require("com.ibm.team.workitem.api.common.WorkItemAttributes");
(function() {
    var WorkItemAttributes = com.ibm.team.workitem.api.common.WorkItemAttributes;
    dojo.declare("com.MTD_OtherTargetType", null, {
      matches: function(workItem, configuration) {
         var target_types = workItem.getValue("target-type-list");
            var isother = "No";
            console.log("Types: '" + target_types + "'");
            for (var i=0; i < target_types.length; i++) {
              console.log("Type: '" + target_types[i] + "'");
               if ( target_types[i] === "target-type.literal.l11" )
                   isother = "Yes";
            }
    if ( isother === "Yes" )
                return true;
    else
        return false;
        }
    });
})();

console.log("Types: '" + target_types + "'") output is correct -> the searched literal is listed in the log:

          !ENTRY com.ibm.team.rtc.common.scriptengine 1 0 2016-11-21 21:13:32.799

          !MESSAGE LOG: 'Types: '|target-type.literal.l11|target-type.literal.l8|''

But the log print inside the 'for' loop shows that var i is looping letter by letter in the var 'target_types' ,

How to loop by values (by literals inside target_types) ?

Thanks, Orna