Class Constraints in system verilog :

Constraints can be declared as class properties.

1. No end-of-line semi-colon

Constraints can enforce dependencies for randomization.

1. Size of dynamic array must equal len property

Dynamic array is now rand. Both size and contents are randomized, but... ...size is randomized first post_randomize and data_rand methods are no longer required.

class randframe;
 local logic [3:0] addr;
 rand local logic [3:0] len;
 rand logic [7:0] data_arr [];

 function new(input logic[3:0] pa);
   addr = pa;
 endfunction

 constraint framelength {
    data_arr.size() == len;
 }

endclass

randframe one = new(.pa(5));

initial begin
  assert(one.randomize() with {len>0; len<=7;});
  ...

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