Feel.Value.YearsAndMonthsDuration (feel v0.1.0)

The FEEL type years and months duration (DMN 1.6, section 10.3.2.3.8).

A whole number of months, positive or negative. A month has no fixed length in seconds, so this type never mixes with days and time duration: the two have no common supertype and are not comparable, except that zero-length durations of both kinds are equal in one section of the specification.

The components FEEL exposes (years, and months from 0 to 11) are computed from the total when read; they are not stored.

Fields

:months - the total number of months, an integer.

Summary

Types

t()

Functions

new(months)

Builds a duration from a total number of months.

parse(text)

Parses a duration string of years and months, as duration("...") and @"..." read it: the lexical space of the XPath yearMonthDuration (DMN 1.6, section 10.3.4.1).

type()

Returns the type descriptor of years and months duration.

value?(arg1)

Returns true for a t/0 with an integer number of months.

Types

t()

@type t() :: %Feel.Value.YearsAndMonthsDuration{months: integer()}

Functions

new(months)

@spec new(integer()) :: t()

Builds a duration from a total number of months.

iex> Feel.Value.YearsAndMonthsDuration.new(13)
%Feel.Value.YearsAndMonthsDuration{months: 13}

parse(text)

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

Parses a duration string of years and months, as duration("...") and @"..." read it: the lexical space of the XPath yearMonthDuration (DMN 1.6, section 10.3.4.1).

It is P, then years (nY), months (nM), or both, in that order, with a leading - for a negative duration. The months are not limited to 11: P26M is P2Y2M. White space around the string is ignored. Returns :error for anything else, which includes a string with days or a time part (P1Y2DT3H: that is not a years and months duration), a bare P, and a number of months beyond 34 digits.

iex> Feel.Value.YearsAndMonthsDuration.parse("P1Y8M")
{:ok, %Feel.Value.YearsAndMonthsDuration{months: 20}}
iex> Feel.Value.YearsAndMonthsDuration.parse("P26M")
{:ok, %Feel.Value.YearsAndMonthsDuration{months: 26}}
iex> Feel.Value.YearsAndMonthsDuration.parse("-P1Y")
{:ok, %Feel.Value.YearsAndMonthsDuration{months: -12}}
iex> Feel.Value.YearsAndMonthsDuration.parse("P1D")
:error
iex> Feel.Value.YearsAndMonthsDuration.parse("P")
:error

type()

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

Returns the type descriptor of years and months duration.

value?(arg1)

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

Returns true for a t/0 with an integer number of months.