Reg data type as Combinational element

module reg_combo_example( a, b, y);

input a, b;

output y;

reg y;

wire a, b;

always @ ( a or b)

begin

y = a & b;

end

endmodule

This gives the same output as that of assign statement, with the only difference that y is declared as  reg.  There  are  distinct  benefits to  have  reg  modeled  as  combinational  element;  reg  type  is useful when a "case" statement is required.