# `Feel.Value.Temporal`
[🔗](https://github.com/FeeJai/BDM/blob/feel-v0.1.0/apps/feel/lib/feel/value/temporal.ex#L1)

Reads the text of a date, a time, a date and time, or a duration, and finds out
which of the five it is.

The string of an `@"..."` literal does not say what it denotes, so the kind is chosen
by its shape (notes 01, A32):

  * an optional `-` and `P` is a duration, a years and months duration when it has
    years or months only and a days and time duration otherwise;
  * a date, a `T`, and a time is a date and time;
  * a date alone is a date;
  * `hh:` is a time.

Each kind is then read by its own `parse/1`, which has the rules for the string and
returns `:error` for one that is not a valid value of the kind, as `@"2020-13-45"`
or `@"25:00:00"`. A string of none of these shapes is `:error` too.

# `t`

```elixir
@type t() ::
  Date.t()
  | Feel.Value.Time.t()
  | Feel.Value.DateTime.t()
  | Feel.Value.YearsAndMonthsDuration.t()
  | Feel.Value.DaysAndTimeDuration.t()
```

A date, a time, a date and time, or a duration.

# `parse`

```elixir
@spec parse(String.t()) :: {:ok, t()} | :error
```

Parses the text of a temporal value of any kind.

    iex> Feel.Value.Temporal.parse("2019-03-31")
    {:ok, ~D[2019-03-31]}
    iex> {:ok, %Feel.Value.Time{hour: 23}} = Feel.Value.Temporal.parse("23:59:00z")
    iex> {:ok, %Feel.Value.DateTime{}} = Feel.Value.Temporal.parse("2012-12-24T23:59:00")
    iex> Feel.Value.Temporal.parse("PT5H")
    {:ok, Feel.Value.DaysAndTimeDuration.new(18_000)}
    iex> Feel.Value.Temporal.parse("-P1Y")
    {:ok, %Feel.Value.YearsAndMonthsDuration{months: -12}}
    iex> Feel.Value.Temporal.parse("2020-13-45")
    :error
    iex> Feel.Value.Temporal.parse("yesterday")
    :error

---

*Consult [api-reference.md](api-reference.md) for complete listing*