angularjs - Pass expression to directive -

i have directive, has directive in it's template.

<nv-select ng-model="from" ng-options="item.name item item in from"></nv-select> 

here try pass along expression ng-options of child directive. unfortunately gives me following error

error: syntax error: token 'as' unexpected token @ column ... 

if put expression in ng-options of child directive's select, works fine. nv-select directive looks this:

function () {   return {     restrict: 'e', // restrict elements     replace: true,     transclude: true,     scope: {       ngmodel: "=",       ngoptions: "&",       placeholder: '@'     },     template: [       '<div class="nv-select">',         '<select ng-model="ngmodel" ng-options="ngoptions" ng-transclude></select>',         '<span class="icon suffix-icon-down">{{ text || placeholder }}</span>',       '</div>'     ].join(''),     link: function (scope, elem, attr) {       var select = elem.find('select'),           copyvalues = function (e) {             if (e.options) {               scope.text = angular.element(e.options[e.selectedindex]).text();             }           };       copyvalues(elem[0]);       elem.bind('click', function (event) {         elem.toggleclass('active');       });       select.bind('change', function (event) {         scope.$apply(function () {           copyvalues(event.target);         });       });     }   }; }; 

nv-select wrapper around <select> enable custom styling.

do have take special considerations when passing along expression? doing wrong?

let's see how ngoptions implemented in angularjs sources. here can find regexp pattern expressions:

var ng_options_regexp = /^\s*(.*?)(?:\s+as\s+(.*?))?(?:\s+group\s+by\s+(.*))?\s+for\s+(?:([\$\w][\$\w\d]*)|(?:\(\s*([\$\w][\$\w\d]*)\s*,\s*([\$\w][\$\w\d]*)\s*\)))\s+in\s+(.*)$/ 

and then

    if (! (match = optionsexp.match(ng_options_regexp))) {       throw error(         "expected ngoptions in form of '_select_ (as _label_)? (_key_,)?_value_ in _collection_'" +         " got '" + optionsexp + "'.");     }      var displayfn = $parse(match[2] || match[1]),         valuename = match[4] || match[6],         keyname = match[5],         groupbyfn = $parse(match[3] || ''),         valuefn = $parse(match[2] ? match[1] : valuename),         valuesfn = $parse(match[7]); 

so can use or write new.