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Programming-Idioms

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Idiom #11 Pick a random element from a list

The list x must be non-empty.

A hand picking a random note in a hat 
Imports System
x(Random.Shared.Next(x.Count))

.NET 6 preview 7 adds a thread-safe global Random instance that reduces the need for custom caching of Random instances.
Imports System
x(New Random().Next(x.Count))

Consider caching the Random instance, as creating an instance is expensive compared to invoking Next().
with Ada.Numerics.Discrete_Random;
subtype Element_Type is Integer;
type List_Type is array (Positive range <>) of Element_Type;

function Pick_Random (X : List_Type) return Element_Type is
   subtype Index_Range  is Positive range X'Range;
   package Random_Index is new
     Ada.Numerics.Discrete_Random (Index_Range);
   Generator : Random_Index.Generator;
begin
   Random_Index.Reset (Generator);
   return X (Random_Index.Random (Generator));
end Pick_Random;
New implementation...
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programming-idioms.org 
x(Random.Shared.Next(x.Count))
x(New Random().Next(x.Count))
subtype Element_Type is Integer;
type List_Type is array (Positive range <>) of Element_Type;

function Pick_Random (X : List_Type) return Element_Type is
   subtype Index_Range  is Positive range X'Range;
   package Random_Index is new
     Ada.Numerics.Discrete_Random (Index_Range);
   Generator : Random_Index.Generator;
begin
   Random_Index.Reset (Generator);
   return X (Random_Index.Random (Generator));
end Pick_Random;
x[rand() % x_length];
(rand-nth x)
std::mt19937 gen;
std::uniform_int_distribution<size_t> uid (0, x.size () - 1);
x[uid (gen)];

std::ranges::sample(x, &result, 1, std::mt19937{std::random_device{}()});
x[Random.Shared.Next(x.Count)]
x[new Random().Next(x.Count)]
x.randomSample(1);
x[new Random().nextInt(x.length)];
Enum.random(x)

lists:nth(rand:uniform(length(X)), X).
ktn_random:pick(X)
call random_number (a)
x(lbound(x) + int(a*ubound(x))

func pickT(x []T) T {
	return x[rand.Intn(len(x))]
}
func pick[T any](x []T) T {
	return x[rand.Intn(len(x))]
}
x[rand.Intn(len(x))]
x.shuffled().first()
(\l g -> l !! fst (randomR (0, length l) g))
(l !!) <$> randomRIO (0, length l - 1)
x[~~(Math.random() * x.length)];
x[Math.floor(Math.random() * x.length)]
if (!x.isEmpty()) {
    Random r = new Random();
    T t = x.get(r.nextInt(x.size()));
}
x.get((int)(Math.random()*x.size()))
x.get(ThreadLocalRandom.current().nextInt(0, x.size()))
list.random()
(nth (random (length x)) x)
x[math.random(#x)]
x[arc4random_uniform(x.count)]
$x[ array_rand($x) ]
element := x.Items[random(x.count)];
element := x[random(length(x))];

my @x = ('a', 'list', 'of', 'random', 'items');
print $x[rand @x];
random.choice(x)
if x: z = choice(x)
x.sample
let mut rng = rand::thread_rng();
let choice = x.choose(&mut rng).unwrap();
x[rand::thread_rng().gen_range(0..x.len())]
val x = List(1, 2, 3, 4)
x.apply(Random.nextInt(x.size))
(list-ref x (random (length x)))
x atRandom