private boolean r_instrum() {
		int among_var;
		// (, line 76
		// [, line 77
		ket = cursor;
		// substring, line 77
		among_var = find_among_b(a_3, 2);
		if (among_var == 0) {
			return false;
		}
		// ], line 77
		bra = cursor;
		// call R1, line 77
		if (!r_R1()) {
			return false;
		}
		switch (among_var) {
		case 0:
			return false;
		case 1:
			// (, line 78
			// call double, line 78
			if (!r_double()) {
				return false;
			}
			break;
		case 2:
			// (, line 79
			// call double, line 79
			if (!r_double()) {
				return false;
			}
			break;
		}
		// delete, line 81
		slice_del();
		// call undouble, line 82
		if (!r_undouble()) {
			return false;
		}
		return true;
	}