let x: string | null = "foo";
assert(null != x);

WARNING AS226: Expression resolves to unusual type 'usize'.
   :
 3 │ assert(null != x);
   │        ~~~~
   └─ in foo.ts(3,8)

ERROR TS2365: Operator '!=' cannot be applied to types 'usize' and '~lib/string/String | null'.
   :
 3 │ assert(null != x);
   │        ~~~~~~~~~
   └─ in foo.ts(3,8)

FAILURE 1 compile error(s)

let data: u128 | null = u128.Max;
assert(data != null);

ERROR TS2322: Type '~lib/as-bignum/assembly/integer/u128/u128 | null' is not assignable to type '~lib/as-bignum/assembly/integer/u128/u128'.
     :
 327 │ assert(data != null);

  @inline @operator('==')
  static eq(a: u128, b: u128): bool {
    return a.hi == b.hi && a.lo == b.lo;
  }

  @inline @operator('!=')
  static ne(a: u128, b: u128): bool {
    return !u128.eq(a, b);
  }