# `Calendrical.DateRangeParseError`

Returned (or raised) by `Calendrical.Date.parse_range/2` when an
input cannot be interpreted as a date range, or when both
endpoints parsed successfully but the resulting range is invalid.

Carries semantic fields only; the human-readable description is
materialised by `message/1`. Pattern-match on `:reason` to branch
on failure category without parsing prose.

### Fields

* `:input` — the raw input that was passed in. A binary for the
  single-string form, a `{from, to}` tuple for the pair form.

* `:reason` — atom describing the failure category. See
  `reason_atoms/0` for the closed set of permitted values.

* `:locale` — the locale the parser tried. Set for failures
  surfaced before sub-parsing (e.g. `:no_separator`).

* `:from`, `:to` — the parsed endpoints. Set when the failure
  occurs after both endpoints parsed successfully
  (e.g. `:inverted`).

* `:cause` — the wrapped inner exception when this error is a
  wrapper for a sub-parser failure (`:from_parse_failed` /
  `:to_parse_failed`). `nil` otherwise.

# `reason`

```elixir
@type reason() :: :no_separator | :inverted | :from_parse_failed | :to_parse_failed
```

# `t`

```elixir
@type t() :: %Calendrical.DateRangeParseError{
  __exception__: term(),
  cause: Exception.t() | nil,
  from: Date.t() | nil,
  input: term(),
  locale: atom() | String.t() | nil,
  reason: reason() | nil,
  to: Date.t() | nil
}
```

---

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