59. Absolute Value

How do you plan to solve it?

module abs8_func (
    input  signed [7:0] a,
    output       [7:0] abs
);
    // ---------- Write function here----------
    function [7:0]abs8;
        input  signed [7:0] num;
        begin
           if(num<0)       abs8 = -num;
           else if (num == -8'sd128) abs8 = num;
           else                      abs8 = num;
        end
    endfunction
    // Function called here
    assign abs = abs8(a);

endmodule