`define PACK_ARRAY(PK_WIDTH,PK_LEN,PK_SRC,PK_DEST)    genvar pk_idx; generate for (pk_idx=0; pk_idx<(PK_LEN); pk_idx=pk_idx+1) begin; assign PK_DEST[((PK_WIDTH)*pk_idx+((PK_WIDTH)-1)):((PK_WIDTH)*pk_idx)] = PK_SRC[pk_idx][((PK_WIDTH)-1):0]; end; endgenerate

`define UNPACK_ARRAY(PK_WIDTH,PK_LEN,PK_DEST,PK_SRC)  genvar unpk_idx; generate for (unpk_idx=0; unpk_idx<(PK_LEN); unpk_idx=unpk_idx+1) begin; assign PK_DEST[unpk_idx][((PK_WIDTH)-1):0] = PK_SRC[((PK_WIDTH)*unpk_idx+(PK_WIDTH-1)):((PK_WIDTH)*unpk_idx)]; end; endgenerate


module example (
    input  [63:0] pack_4_16_in,
    output [31:0] pack_16_2_out
    );

wire [3:0] in [0:15];
`UNPACK_ARRAY(4,16,in,pack_4_16_in)

wire [15:0] out [0:1];
`PACK_ARRAY(16,2,in,pack_16_2_out)