Insert an element e into the set x.
x := x + [e];
Include(x,e);
#include <set>
x.insert(e);
x.add(e);
x[e] = struct{}{}
x[e] = true
import java.util.Set;
x.add(e)
use Set::Scalar;
$x = Set::Scalar->new; $e = 'an element'; $x->insert($e);
require 'set'
x << e
use std::collections::HashSet
No security, no password. Other people might choose the same nickname.
