unshift
Prepends one or more values to the beginning of an array.
Prepends the listed values to the front of the array, preserving
argument order: unshift(@a, 1, 2, 3) yields (1, 2, 3, @original).
Array arguments are flattened. Returns the new number of elements.
Internally, values are inserted in reverse order to achieve the
correct final ordering.
Synopsis
unshift @array, $value;
unshift @array, $v1, $v2, $v3;
unshift @array, @more_values;
my $new_len = unshift @array, $value;