public final ExtDeclarationContext extDeclaration() throws RecognitionException {
		ExtDeclarationContext _localctx = new ExtDeclarationContext(_ctx, getState());
		enterRule(_localctx, 66, RULE_extDeclaration);
		int _la;
		try {
			enterOuterAlt(_localctx, 1);
			{
			setState(594); match(T__39);
			setState(596);
			_la = _input.LA(1);
			if (_la==T__38) {
				{
				setState(595); typeVarTuple();
				}
			}

			setState(598); match(ID);
			setState(602);
			_errHandler.sync(this);
			_la = _input.LA(1);
			while (_la==T__35) {
				{
				{
				setState(599); annotation();
				}
				}
				setState(604);
				_errHandler.sync(this);
				_la = _input.LA(1);
			}
			setState(605); match(T__52);
			setState(609);
			_errHandler.sync(this);
			_la = _input.LA(1);
			while ((((_la) & ~0x3f) == 0 && ((1L << _la) & ((1L << T__43) | (1L << T__32) | (1L << T__11) | (1L << T__2))) != 0)) {
				{
				{
				setState(606); extElement();
				}
				}
				setState(611);
				_errHandler.sync(this);
				_la = _input.LA(1);
			}
			setState(612); match(T__21);
			}
		}
		catch (RecognitionException re) {
			_localctx.exception = re;
			_errHandler.reportError(this, re);
			_errHandler.recover(this, re);
		}
		finally {
			exitRule();
		}
		return _localctx;
	}