code: public static MutableShort fromExternal(final Supplier<Short> s, final Consumer<Short> c) {
          return new MutableShort() {
              @Override
              public short getAsShort() {
                  return s.get();
              }
  
              @Override
              public Short get() {
                  return getAsShort();
              }
  
              @Override
              public MutableShort set(final short value) {
                  c.accept(value);
                  return this;
              }
          };
      }
docs: Construct a MutableShort that gets and sets an external value using the provided Supplier and Consumer
  
  e.g.
  <pre>
  {@code
  MutableShort mutable = MutableShort.fromExternal(()->!this.value,val->!this.value);
  }
  </pre>
  
  
  @param s Supplier of an external value
  @param c Consumer that sets an external value
  @return MutableShort that gets / sets an external (mutable) value