User guide

24-27

SystemVerilog Testbench Constructs

first

Assigns the value of the smallest or alphabetically first entry in

the array. Returns 0 if the array is empty and returns 1 if the array

contains a value.

last

Assigns the value of the largest or alphabetically last entry in the

array. Returns 0 if the array is empty and returns 1 if the array

contains a value.

Finds the entry whose index is greater than the given index. If

there is a next entry, the index variable is assigned the index of

the next entry, and the function returns 1. Otherwise, variable is

unchanged, and the function returns 0

Finds the entry whose index is smaller than the given index. If

there is a previous entry, the index variable is assigned the index

of the previous entry, and the function returns 1. Otherwise,

variable is unchanged, and the function returns 0.

The following example shows how to use these methods.

program p;

logic [7:0] a[string];

string s_index;

initial begin

a["sa"] = 8;

a["bb"] = 15;

a["ec"] = 29;

a["d"] = 32;

a["e"] = 45;

$display("number of entries = %0d",a.num);

if(a.exists("sa"))

$display("string \"sa\" is in a");

if(a.first(s_index))

begin