Foreach loop in SystemVerilog

The foreach loop in SystemVerilog iterates over the array element. Unlike for loop, foreach loop does not require initialization, condition, or update value.

Syntax:

foreach (variable[iterator]) begin
  ...
end

foreach loop in the single-dimensional (1D) array

module foreach_example;
  int array[5] = '{100, 200, 300, 400, 500};
  initial begin
    foreach (array[i]) begin
      $display("array[%0d] = %0d", i, array[i]);
    end
  end
endmodule

Output:

array[0] = 100
array[1] = 200
array[2] = 300
array[3] = 400
array[4] = 500

foreach loop in the multidimensional array

foreach loop in two dimensional (2D) array

module foreach_example;
  int array[6][2] = '{'{1, 100}, '{2, 200}, '{3, 300}, '{4,400}, '{5, 500}, '{6, 600}};
  initial begin
    foreach (array[i,j]) begin
      $display("array[%0d][%0d] = %0d", i,j, array[i][j]);
    end
  end
endmodule

Output:

array[0][0] = 1
array[0][1] = 100
array[1][0] = 2
array[1][1] = 200
array[2][0] = 3
array[2][1] = 300
array[3][0] = 4
array[3][1] = 400
array[4][0] = 5
array[4][1] = 500
array[5][0] = 6
array[5][1] = 600

foreach loop in the three dimensional (3D) array

module foreach_example;
  int array[3][3][3] = '{'{'{1, 10, 100}, '{2, 20, 200}, '{3, 30, 300}},
                         '{'{4, 40, 400}, '{5, 50, 500}, '{6, 60, 600}},
                         '{'{7, 70, 700}, '{8, 80, 800}, '{9, 90, 900}}
                        };
  initial begin
    foreach (array[i,j, k]) begin
      $display("array[%0d][%0d][%0d] = %0d", i,j, k, array[i][j][k]);
    end
  end
endmodule

Output:

array[0][0][0] = 1
array[0][0][1] = 10
array[0][0][2] = 100
array[0][1][0] = 2
array[0][1][1] = 20
array[0][1][2] = 200
array[0][2][0] = 3
array[0][2][1] = 30
array[0][2][2] = 300
array[1][0][0] = 4
array[1][0][1] = 40
array[1][0][2] = 400
array[1][1][0] = 5
array[1][1][1] = 50
array[1][1][2] = 500
array[1][2][0] = 6
array[1][2][1] = 60
array[1][2][2] = 600
array[2][0][0] = 7
array[2][0][1] = 70
array[2][0][2] = 700
array[2][1][0] = 8
array[2][1][1] = 80
array[2][1][2] = 800
array[2][2][0] = 9
array[2][2][1] = 90
array[2][2][2] = 900

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