In reply to poonamnlwd:
This does not matter. See the code example below.
package my_sv_types;
typedef struct packed {
logic val;
logic [7:0] dat;
} abc_sv_t;
typedef abc_sv_t [6] a;
typedef a [4] b;
typedef struct packed {
b efg;
} bcd_sv_t;
endpackage
module tb;
import my_sv_types::*;
logic clk;
a sig1 = '{'{1'b0, 8'h55}, '{1'b0, 8'h55}, '{1'b0, 8'h55}, '{1'b0, 8'h55}, '{1'b0, 8'h55}, '{1'b0, 8'h55}};
b sig2;
abc_sv_t [5:0] sig3;
bcd_sv_t [3:0] sig4;
abc_sv_t [0:5] sig5;
bcd_sv_t [0:3] sig6;
initial begin
sig3 = sig1;
#10;
sig5 = sig1;
#10;
end
endmodule