Decide when to 'templateUrl' of AngularJS directive in the link function - angularjs

Question

Is it possible to decide whether to use templateUrl parameter in the link function of AngularJS directive?
Suppose I have the following directive:
app.directive('sitesAndImprovements', function() {
return {
restrict: 'E',
replace:true,
templateUrl: '<path-to-file>/site-and-improvments.html',
link: function (scope, elem, attrs) {
scope.testClick = function() {
var myScope = scope;
//debugger;
}
scope.constructionCompleteClick = function () {
if (scope.construction_complete == 'Yes') {
scope.hold_back = '';
scope.percent_complete = 100;
} else
if (scope.construction_complete == 'No') {
scope.hold_back = '1';
if (scope.percent_complete == 100) {
scope.percent_complete = '';
}
}
}
scope.calcTotal = function () {
var total;
total = (scope.main || 0) + (scope.second || 0) + (scope.third || 0) + (scope.fourth || 0);
scope.total = total || null;
}
}
}
})
I want to control whether to use or not to use the templateUrl and also the replace parameters in the link() function.
This is because I already implemented this directive in about 10+ places without using templateUrl and now I want to start using this feature, but I don't want to make changes to existing and working code.
Is that possible and how?
Tarek

Answer 1

I don't think you can do that in the link, but I believe you can turn templateUrl into a function that can return different values for the directive.
Try doing something like this for your templateUrl:
templateUrl: function() {
if (someCondition) {
return '<path-to-file>/site-and-improvments.html';
} else {
return null;
}
},

Answer 2

app.directive('sitesAndImprovements', function() {
return {
restrict: 'E',
replace:function(){
if (aCondition){
return true;
} else {
return false;
}
},
templateUrl: function(){
if (aCondition){
return '<path-to-file>/site-and-improvments.html';
} else {
return undefined;
}
},
link: function (scope, elem, attrs) {
scope.testClick = function() {
var myScope = scope;
//debugger;
}
scope.constructionCompleteClick = function () {
if (scope.construction_complete == 'Yes') {
scope.hold_back = '';
scope.percent_complete = 100;
} else
if (scope.construction_complete == 'No') {
scope.hold_back = '1';
if (scope.percent_complete == 100) {
scope.percent_complete = '';
}
}
}
scope.calcTotal = function () {
var total;
total = (scope.main || 0) + (scope.second || 0) + (scope.third || 0) + (scope.fourth || 0);
scope.total = total || null;
}
}
}
})
Explanation : As stated in the source code, the template will be compiled only if templateUrl is given :
...
if (directive.templateUrl) {
hasTemplate = true;
assertNoDuplicate('template', templateDirective, directive, $compileNode);
templateDirective = directive;
if (directive.replace) {
replaceDirective = directive;
}
// eslint-disable-next-line no-func-assign
nodeLinkFn = compileTemplateUrl(directives.splice(i, directives.length - i), $compileNode,
...
Please, note that aCondition could be an attribute passed to the directive to enable/disable the templateUrl and the replace. Also, keep in mind that the replace is deprecated.