Calling a function in AngularJS service from the same service?

I have an AngularJS service defined in the following way

angular.module('myService').service('myService', function() {
  this.publicFunction(param) {
    ...
  };

  this.anotherPublicFunction(param) {
    // how to call publicFunction(param)?
    ...
  };
});    

and I would like to call the first function both from outside the service (which works fine by myService.publicFunction(xxx)) and from another function in the same service, i.e. anotherPublicFunction. Neither one of this.publicFunction(param) or myService.publicFunction(param) won't work from within the second function, and I can understand that.

EDIT:
Actually the whole problem was caused by something you can't reproduce with my example alone. I passed the second function as a callback parameter to another function in a separate controller, and when it is called, the reference to this doesn't work.

E.g.

anotherService.someCall('a', 123, myService.anotherPublicFunction);

fails inside anotherPublicFunction because this can't be resolved.

I've written a Plunker to show the problem: http://plnkr.co/edit/rrRs9xnZTNInDVdapiqF?p=info

(I'll still leave the question here in case it will help someone else.)

I know I could get around the problem by using a reference to the service or the first function like this

var ms = this;
this.anotherPublicFunction(param) {
  ms.publicFunction(param);
  ...
};

or this

var pf = this.publicFunction;
this.anotherPublicFunction(param) {
  pf(param);
  ...
};

but both seem like dirty hacks.

Is there a good way to call the first function from the second one in this case? Or am I doing something totally wrong in the first place to have a service like this?

I found these questions with good answers:

• Angularjs share functions inside service
• AngularJs call an internal service function from self

but they differ from my problem since one of them has a separate, internal function that was to be called, and the other one was using a factory instead of a service.

EDIT:

After posting this I immediately realized I could also do this:

var actualWork = function(param) {
  ...
}

this.publicFunction(param) {
  actualWork(param);
};

this.anotherPublicFunction(param) {
  actualWork(param);
  ...
};

which doesn't seem quite as bad as the other options so far... Are there better approaches?

I think the best way is to go like this:

var myFunctions = 
{

    myFunc1: function(param) {

    },

    myFunc2: function(param) {
       return foo + myFunctions.myFunc1(param)// do some stuff with the first function        
    }

}
return myFunctions;

because I think if you use this, it may get conflict with the scope where you use the service.

I ran into this problem within my own angular coding and opted to use this form of the solution:

angular.module('myService').service('myService', function() {
  var myService = this;
  myService.publicFunction(param) {
    ...
  };

  myService.anotherPublicFunction(param) {
    myService.publicFunction(param);
    ...
  };
});

I preferred this approach because in my code I use publicFunction and inside of anotherPublicFunction I loop over several params that need to call publicFunction as part of the process.

Sounds good but what do you do when this is no longer = the service ?

This is the case in the following example:

return {

        myFunc1: function(param) {

        },

        myFunc2: function(param) {

            scope.$watchCollection(param,function(v) {

              return foo + this.myFunc1(param)// do some stuff with the first function 

            }       
        }

}

Because of function(v) { you are now in another function within the function and this is no longer the service but the window.

You can just return an object from within your service like

return {

    myFunc1: function(param) {

    },

    myFunc2: function(param) {
       return foo + this.myFunc1(param)// do some stuff with the first function        
    }

}

So you access it from the outside with service.myFunc1 and from inside its internal functions with this.

You can set 'this' as variable

angular.module('myService').service('myService', function() {
  var that = this;
  this.publicFunction(param) {
    ...
  };

  this.anotherPublicFunction(param) {
    that.publicFunction(param);
  };
});