Concept and usage of “this” is simple but important in test bench development using system verilog. I would like to share some insights on this concept.

The this keyword is an implicit argument to a method that refers to the current object. 

Let’s understand this concept with the following example.

class concept_this ;

  int a ;

  function new (int a);

    this.a = a;

  endfunction : new

endclass

program main;

  concept_this obj_th = new (777);

  initial begin

    $display ("obj_th.a = %d", obj_th.a);

  end

endprogram

In above example we can see that ‘a’ is a property of class “concept_this”. When we initialize the memory for class, we have passed an integer value ‘777’ to its class constructor i.e. function new(). The variable ‘a’ is local to class instance “obj_th and is now 777 as we have passed this from it’s class constructor.