• Lisp

(defun ins (lst x i)
 (if (zerop i) (cons x lst)
     (cons (car lst) (ins (cdr lst) x (- i 1)))))

(setf s (ins s x i))

• C++

s.insert (s.begin () + i, x);

• C#

s.Insert(i, x);

• D

s.insertInPlace(i, x);

• Dart

s.insert(i, x);

• Elixir

List.insert_at(s, i, x)

• Erlang

{Left, Right} = lists:split(I-1, S),
Left ++ [X|Right].

• Fortran

integer, dimension(:), allocatable :: s

s = [s(1:i-1), x, s(i:)]

• Go

s = append(s, 0)
copy(s[i+1:], s[i:])
s[i] = x

• Go

s = slices.Insert(s, i, x)

• Haskell

take i s ++ x : drop i s

• JS

s.splice(i, 0, x);

• Java

int a = 0, n = s.length;
Class<?> c = s.getClass().getComponentType();
T t[] = (T[]) newInstance(c, n + 1);
arraycopy(s, a, t, a, i);
t[i] = x;
arraycopy(s, i, t, i + 1, n - i);

• Java

int a = 0, n = s.length,
    t[] = new int[n + 1];
arraycopy(s, a, t, a, i);
t[i] = x;
arraycopy(s, i, t, i + 1, n - i);

• Java

s.add(i, x);

• Kotlin

s.add(i, x)

• Lua

table.insert(s,i,x)

• PHP

array_splice($s, $i, 0, $x);

• Pascal

s.Insert(i, x)

• Perl

splice(@s, $i, 0, $x);

• Python

s.insert(i, x)

• Ruby

s.insert(i, x)

• Rust

s.insert(i, x);

• VB

s.Insert(i,x)