Message Format 2

The repo implements localization by the Message Format 2 specification (release LDML48.2) of the Message Format Working Group (MFWG):

The project implements the following packages (temporary layout):

• go.expect.digital/mf2/template executes MF2 templates (WIP)
• go.expect.digital/mf2/parse parses MF2 templates
• go.expect.digital/mf2/builder builds MF2 templates (WIP)
• CLI to extract and update localized message strings (NOT IMPLEMENTED)

Requirements

• Golang 1.25+
• IANA Time Zone database - one of:
  • the directory or uncompressed zip file named by the ZONEINFO environment variable
  • on a Unix system, the system standard installation location
  • $GOROOT/lib/time/zoneinfo.zip
  • the time/tzdata package

Features

Function registry

List of the default functions registered in the function registry. The functions support localized formatting.

Function	Signature	Option	Status
currency	format	currency	❌
currency	format	currencyDisplay (narrowSymbol, symbol, name, code, never)	❌
currency	format	currencySign (accounting, standard)	❌
currency	format	fractionDigits	❌
currency	format	maximumSignificantDigits	❌
currency	format	minimumIntegerDigits	❌
currency	format	minimumSignificantDigits	❌
currency	format	roundingIncrement	❌
currency	format	roundingMode (ceil, floor, expand, trunc, halfCeil, halfFloor, halfExpand, halfTrunc, halfEven)	❌
currency	format	roundingPriority (auto, morePrecision, lessPrecision)	❌
currency	format	trailingZeroDisplay (auto, stripIfInteger)	❌
currency	format	useGrouping (auto, always, never, min2)	❌
date	format	calendar	❌
date	format	fields (weekday ✅︎, day-weekday ✅︎, month-day ✅︎, month-day-weekday ❌, year-month-day ✅︎, year-month-day-weekday ❌)	❌
date	format	length (long, medium, short)	❌
date	format	timeZone	❌
datetime	format	calendar	❌
datetime	format	dateFields (weekday ✅︎, day-weekday ✅︎, month-day ✅︎, month-day-weekday ❌, year-month-day ✅︎, year-month-day-weekday ❌)	❌
datetime	format	dateLength (long, medium, short)	❌
datetime	format	hour12 (true, false)	❌
datetime	format	timePrecision (hour, minute, second)	❌
datetime	format	timeZone	❌
datetime	format	timeZoneStyle (long, short)	❌
integer	format	maximumSignificantDigits	✅︎
integer	format	minimumIntegerDigits	✅︎
integer	format	signDisplay (auto, always, exceptZero, negative, never)	✅︎
integer	format	useGrouping (auto, always, never, min2)	✅︎
integer	match	maximumSignificantDigits	✅︎
integer	match	minimumIntegerDigits	✅︎
integer	match	select (plural, ordinal, exact)	✅︎
number	format	maximumFractionDigits	✅︎
number	format	maximumSignificantDigits	✅︎
number	format	minimumFractionDigits	✅︎
number	format	minimumIntegerDigits	✅︎
number	format	minimumSignificantDigits	✅︎
number	format	roundingIncrement	✅︎
number	format	roundingMode (ceil, floor, expand, trunc, halfCeil, halfFloor, halfExpand, halfTrunc, halfEven)	❌
number	format	roundingPriority (auto, morePrecision, lessPrecision)	❌
number	format	signDisplay (auto, always, exceptZero, negative, never)	✅︎
number	format	trailingZeroDisplay (auto, stripIfInteger)	❌
number	format	useGrouping (auto, always, never, min2)	✅︎
number	match	maximumFractionDigits	✅︎
number	match	maximumSignificantDigits	✅︎
number	match	minimumFractionDigits	✅︎
number	match	minimumIntegerDigits	✅︎
number	match	minimumSignificantDigits	✅︎
number	match	select (plural, ordinal, exact)	✅︎
offset	format	add	❌
offset	format	subtract	❌
offset	match	add	❌
offset	match	subtract	❌
percent	format	maximumFractionDigits	❌
percent	format	maximumSignificantDigits	❌
percent	format	minimumFractionDigits	❌
percent	format	minimumSignificantDigits	❌
percent	format	roundingMode (ceil, floor, expand, trunc, halfCeil, halfFloor, halfExpand, halfTrunc, halfEven)	❌
percent	format	roundingPriority (auto, morePrecision, lessPrecision)	❌
percent	format	signDisplay (auto, always, exceptZero, negative, never)	❌
percent	format	trailingZeroDisplay (auto, stripIfInteger)	❌
percent	format	useGrouping (auto, always, never, min2)	❌
percent	match		❌
string	format		✅︎
string	match		✅︎
time	format	calendar	❌
time	format	hour12 (true, false)	❌
time	format	precision (hour, minute, second)	❌
time	format	timeZone	❌
time	format	timeZoneStyle (long, short)	❌
unit	format	maximumFractionDigits	❌
unit	format	maximumSignificantDigits	❌
unit	format	minimumFractionDigits	❌
unit	format	minimumIntegerDigits	❌
unit	format	minimumSignificantDigits	❌
unit	format	roundingIncrement	❌
unit	format	roundingMode (ceil, floor, expand, trunc, halfCeil, halfFloor, halfExpand, halfTrunc, halfEven)	❌
unit	format	roundingPriority (auto, morePrecision, lessPrecision)	❌
unit	format	signDisplay (auto, always, exceptZero, negative, never)	❌
unit	format	unit	❌
unit	format	unitDisplay (short, narrow, long)	❌
unit	format	usage	❌
unit	format	useGrouping (auto, always, never, min2)	❌