class Register ;
  string name;
  rand bit [3:0] rank;
  rand bit [3:0] pages;  
  function new(string name);
    this.name = name;
  endfunction
  function void print();
    $display("name=%s rank=%0d pages=%0d",name, rank, pages);
  endfunction
endclass

module tb;
  Register rt[4];
  string name_arr[4]={"alexa","siri","google home","cortana"};
  initial begin
    $display(
      "---------initial value-----------"
    );
    foreach (rt[i]) begin
      rt[i]=new(name_arr[i]);
    rt[i].randomize();
    rt[i].print;
    end
     $display(
      "---------sort by name------------"
    );
    rt.sort (x) with (x.name);
    foreach (rt[i]) rt[i].print;
    $display(
      "---------sort by rank,pages---------"
    );
    rt.sort (x) with ({x.rank,x.pages});
    foreach (rt[i]) rt[i].print;
    $display(
      "---------sort by pages------------"
    );
    rt.sort (x) with (x.pages);
    foreach(rt[i]) rt[i].print;
  end
endmodule
 

# Loading sv_std.std
# Loading work.testbench_sv_unit(fast)
# Loading work.tb(fast)
# 
# vsim -voptargs=+acc=npr
# run -all
# ---------initial value-----------
# name=alexa rank=13 pages=11
# name=siri rank=11 pages=15
# name=google home rank=12 pages=10
# name=cortana rank=8 pages=3
# ---------sort by name------------
# name=alexa rank=13 pages=11
# name=cortana rank=8 pages=3
# name=google home rank=12 pages=10
# name=siri rank=11 pages=15
# ---------sort by rank,pages---------
# name=cortana rank=8 pages=3
# name=siri rank=11 pages=15
# name=google home rank=12 pages=10
# name=alexa rank=13 pages=11
# ---------sort by pages------------
# name=cortana rank=8 pages=3
# name=google home rank=12 pages=10
# name=alexa rank=13 pages=11
# name=siri rank=11 pages=15
# exit
# End time: 07:55:56 on Mar 31,2022, Elapsed time: 0:00:01
# Errors: 0, Warnings: 1