Returns the canonical unit name for a unit

Arguments

• unit_string is any string representing a unit such as light_year_per_week.

Returns

• {:ok, canonical_name} or

• {:error, {exception, reason}}

Examples

iex> Cldr.Unit.Parser.canonical_unit_name "meter"
{:ok, :meter}

iex> Cldr.Unit.Parser.canonical_unit_name "meter meter"
{:ok, :square_meter}

iex> Cldr.Unit.Parser.canonical_unit_name "meter per kilogram"
{:ok, "meter_per_kilogram"}

iex> Cldr.Unit.Parser.canonical_unit_name "meter kilogram"
{:ok, "kilogram_meter"}

iex> Cldr.Unit.Parser.canonical_unit_name "meter kilogram per fluxom"
{:error, {Cldr.UnknownUnitError, "Unknown unit was detected at \"fluxom\""}}

Returns the canonical unit name for a unit or raises on error

Arguments

• unit_string is any string representing a unit such as light_year_per_week.

Returns

• {:ok, canonical_name} or

• raises an exception

Examples

iex> Cldr.Unit.Parser.canonical_unit_name! "meter"
:meter

iex> Cldr.Unit.Parser.canonical_unit_name! "meter meter"
:square_meter

iex> Cldr.Unit.Parser.canonical_unit_name! "meter per kilogram"
"meter_per_kilogram"

iex> Cldr.Unit.Parser.canonical_unit_name! "meter kilogram"
"kilogram_meter"

iex> Cldr.Unit.Parser.canonical_unit_name "curr-usd"
{:ok, "curr_usd"}

iex> Cldr.Unit.Parser.canonical_unit_name "curr-usd-per-kilogram"
{:ok, "curr_usd_per_kilogram"}

=> Cldr.Unit.Parser.canonical_unit_name! "meter kilogram per fluxom"
** (CaseClauseError) no case clause matching: {:error,
    {Cldr.UnknownUnitError, "Unknown unit was detected at "fluxom""}}

@spec parse_unit(String.t()) ::
  {:ok, [Cldr.Unit.base_conversion()]}
  | {:ok, {[Cldr.Unit.base_conversion()], [Cldr.Unit.base_conversion()]}}
  | {:error, {module(), String.t()}}

Parses a unit name expressed as a string and returns the parsed name or an error.

Arguments

• unit_string is a unit name (such as "meter") as a String.t()

Returns

• {:ok, normalized_unit} or

• {:error, {exception, reason}}

Notes

A normalised unit is a 2-tuple with the first element a list of standard units that are before the first "per" in the unit name. The second element is a list of standard units after the first "per" (if any).

The structure of the standard unit is {standard_unit, conversion_to_base_unit}.

This function is not normally called by consumers of this library. It is called by Cldr.Unit.validate_unit/1 which is the main public API.

Example

iex> Cldr.Unit.Parser.parse_unit "kilogram per light year"
{:ok,
 {[
    {:kilogram,
     %Cldr.Unit.Conversion{
       base_unit: [:kilogram],
       factor: 1,
       offset: 0
     }}
  ],
  [
    {:light_year,
     %Cldr.Unit.Conversion{
       base_unit: [:meter],
       factor: 9460730472580800,
       offset: 0
     }}
  ]}}