[time.zone.exception.nonexist]

# 30 Time library [[time]](./#time)

## 30.11 Time zones [[time.zone]](time.zone#exception.nonexist)

### 30.11.3 Exception classes [[time.zone.exception]](time.zone.exception#nonexist)

#### 30.11.3.1 Class nonexistent_local_time [time.zone.exception.nonexist]

namespace std::chrono {class nonexistent_local_time : public runtime_error {public:template<class Duration> nonexistent_local_time(const local_time<Duration>& tp, const local_info& i); };}

[1](#1)

[#](http://github.com/Eelis/draft/tree/9adde4bc1c62ec234483e63ea3b70a59724c745a/source/time.tex#L9096)

nonexistent_local_time is thrown when
an attempt is made
to convert a non-existent local_time to a sys_time without specifying choose​::​earliest or choose​::​latest[.](#1.sentence-1)

[ð](#lib:nonexistent_local_time,constructor)

`template<class Duration>
  nonexistent_local_time(const local_time<Duration>& tp, const local_info& i);
`

[2](#2)

[#](http://github.com/Eelis/draft/tree/9adde4bc1c62ec234483e63ea3b70a59724c745a/source/time.tex#L9109)

*Preconditions*: i.result == local_info​::​nonexistent is true[.](#2.sentence-1)

[3](#3)

[#](http://github.com/Eelis/draft/tree/9adde4bc1c62ec234483e63ea3b70a59724c745a/source/time.tex#L9113)

*Effects*: Initializes the base class with a sequence of char equivalent to that produced by os.str() initialized as shown below:ostringstream os;
os << tp << " is in a gap between\n"<< local_seconds{i.first.end.time_since_epoch()} + i.first.offset << ' '<< i.first.abbrev << " and\n"<< local_seconds{i.second.begin.time_since_epoch()} + i.second.offset << ' '<< i.second.abbrev << " which are both equivalent to\n"<< i.first.end << " UTC";

[4](#4)

[#](http://github.com/Eelis/draft/tree/9adde4bc1c62ec234483e63ea3b70a59724c745a/source/time.tex#L9129)

[*Example [1](#example-1)*: #include <chrono>#include <iostream>int main() {using namespace std::chrono; try {auto zt = zoned_time{"America/New_York",
 local_days{Sunday[2]/March/2016} + 2h + 30min}; } catch (const nonexistent_local_time& e) { std::cout << e.what() << '\n'; }}

Produces the output:

```
2016-03-13 02:30:00 is in a gap between
2016-03-13 02:00:00 EST and
2016-03-13 03:00:00 EDT which are both equivalent to
2016-03-13 07:00:00 UTC

```

â *end example*]
