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

The FEEL type `days and time duration` (DMN 1.6, section 10.3.2.3.7).

A number of seconds, positive or negative, with a fractional part. A day is
exactly 86,400 seconds; there are no calendar or daylight-saving effects. This
type never mixes with `years and months duration`.

The components FEEL exposes (`days`, `hours`, `minutes`, `seconds`) are
computed from the total when read; they are not stored.

## Fields

  * `:seconds` - the total number of seconds, a `t:Feel.Value.Number.t/0`.

# `t`

```elixir
@type t() :: %Feel.Value.DaysAndTimeDuration{seconds: Feel.Value.Number.t()}
```

# `new`

```elixir
@spec new(Feel.Value.Number.t() | integer()) :: t()
```

Builds a duration from a total number of seconds.

Accepts an integer or a `Feel.Value.Number`. Raises `FunctionClauseError` for
anything else, including a non-finite decimal.

    iex> Feel.Value.DaysAndTimeDuration.new(90_000).seconds |> Decimal.to_integer()
    90000

# `parse`

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

Parses a duration string of days and time, as `duration("...")` and `@"..."` read it:
the lexical space of the XPath `dayTimeDuration` (DMN 1.6, section 10.3.4.1).

It is `P`, then days (`nD`), then `T` with hours (`nH`), minutes (`nM`) and seconds
(`nS`, which may have a fraction), in that order, with a leading `-` for a negative
duration. Every part is optional, but one is needed, and `T` needs one of the parts
after it. The parts are not limited to their usual range: `P0DT25H` is one day and one
hour. White space around the string is ignored. Returns `:error` for anything else,
which includes a years or months part (`P1Y` is a years and months duration), and a
number of seconds beyond 34 digits.

The seconds are exact: the parts are added as integers, so the 28 digits that the
`Decimal` context rounds to do not matter.

    iex> Feel.Value.DaysAndTimeDuration.parse("P1DT2H")
    {:ok, Feel.Value.DaysAndTimeDuration.new(93_600)}
    iex> Feel.Value.DaysAndTimeDuration.parse("-PT5H30M")
    {:ok, Feel.Value.DaysAndTimeDuration.new(-19_800)}
    iex> {:ok, duration} = Feel.Value.DaysAndTimeDuration.parse("PT1.50S")
    iex> Decimal.to_string(duration.seconds)
    "1.50"
    iex> Feel.Value.DaysAndTimeDuration.parse("P0DT25H") ==
    ...>   Feel.Value.DaysAndTimeDuration.parse("P1DT1H")
    true
    iex> Feel.Value.DaysAndTimeDuration.parse("P1Y")
    :error
    iex> Feel.Value.DaysAndTimeDuration.parse("PT")
    :error

# `type`

```elixir
@spec type() :: Feel.Type.t()
```

Returns the type descriptor of `days and time duration`.

# `value?`

```elixir
@spec value?(term()) :: boolean()
```

Returns `true` for a `t:t/0` with a finite number of seconds.

---

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