Using the call method

This is a hidden gem in Dart. It enables you to give a parameter to an object, thereby invoking the call method from the object's class.

How to do it...

See its usage in the call project, as shown in the following code:

var u = "Julia";

void main() {
  var embr = new Embrace(5);

The call method can be used in the following ways:

1. Invoke call, as shown in the following code:

     embr(u); // callable method!
     var m = new Mult();
     print(m(3, 4));
   }
   
   class Embrace {
     // see code in recipe: Using reflection

2. Define the call method, as shown in the following code:

     call(var user) { print("$user is called, and hugged with strength $strength!"); }
    }
   
   class Mult{
     call(int a, int b) => a * b;
   }

We get the following output on the screen:

Julia is called, and hugged with strength 5!

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How it works...

We pass the value u to the embr object in the embr(u) call, which invokes the call method. This method defines what the instances of your class do when invoked as functions via the...