Type Alias ssi_claims::chrono::offset::MappedLocalTime

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pub type MappedLocalTime<T> = LocalResult<T>;

Expand description

The result of mapping a local time to a concrete instant in a given time zone.

The calculation to go from a local time (wall clock time) to an instant in UTC can end up in three cases:

A single, simple result.
An ambiguous result when the clock is turned backwards during a transition due to for example DST.
No result when the clock is turned forwards during a transition due to for example DST.

When the clock is turned backwards it creates a fold in local time, during which the local time is ambiguous. When the clock is turned forwards it creates a gap in local time, during which the local time is missing, or does not exist.

Chrono does not return a default choice or invalid data during time zone transitions, but has the MappedLocalTime type to help deal with the result correctly.

The type of T is usually a DateTime but may also be only an offset.

Aliased Type§

enum MappedLocalTime<T> {
    Single(T),
    Ambiguous(T, T),
    None,
}

Variants§

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Single(T)

The local time maps to a single unique result.

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Ambiguous(T, T)

The local time is ambiguous because there is a fold in the local time.

This variant contains the two possible results, in the order (earliest, latest).

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None

The local time does not exist because there is a gap in the local time.