The purpose of javascript uglify is to make our javascript files size smaller. Smaller means faster load on web. When I tried to uglify my javascript that contain angular codes, I got this error

error:unpr Unknown Provider Unknown provider: aProvider <- a

I found that the error is caused by variable named changing by uglify method (see mangle option true as default setting). It can be turned off but I don't want to. Below is the code that caused error

[code language="javascript"] var $injector = angular.injector(['ng', 'myapp']); $injector.invoke(function ($rootScope, $compile) { ... }); [/code]

Uglify changed $rootScope and $compile name to others that caused the error. So, the solution is simple, I need to keep those name exist by adding their names before their function parameters.

[code language="javascript"] var $injector = angular.injector(['ng', 'myapp']); $injector.invoke(['$rootScope', '$compile', function ($rootScope, $compile) { ... }]); [/code]

This is how I solved the error and become my best practice when coding in Angular JS.