When working with dates it automatically localizes them, i.e. my local date would be YYYY-MM-DD while with en-US locale I would receive DD/MM/YY.
When working with length, area, weight, volume, temperature, time and their compound units like length-per-time I can't find a similar feature in Intl API. I've been searching specs and github for whole day, but the closest thing I found was https://github.com/tc39/ecma402/issues/32 :
var f = Intl.UnitFormat(navigator.languages, {
units: {
{type: 'length', unit: 'bestFit'},
}
});
f.format(2048); // would return '2 km' in en-US
Which seems to be gone after merging into "Intl.NumberFormat rev. 2".
So is there a way to avoid mapping every existing locale with every existing unit like in this example?:
const format = unit => value =>
new Intl.NumberFormat("en", {
style: "unit",
unit,
notation: "compact",
maximumSignificantDigits: 3
})
.format(value)
function fakeBestFit(value, locale) {
// if US or any other imeprial system based locale
if (locale || navigator.language === 'en-US') {
const mile = 1609.34
const yard = 0.9143977272588
// const inch = ...
// const foot = ...
if (value >= mile) {
return format("mile")(value / mile)
} else if (value >= yard) {
return format("yard")(value / yard)
} else {
// other units for locale i.e. inches and feet
}
} else {
// for metric countries
return format("meter")(value)
}
}
console.log('expected: 1 m, received: ' + fakeBestFit(1))
console.log('expected: 1 km, received: ' + fakeBestFit(1000))
console.log('expected: 1 Mm, received: ' + fakeBestFit(1000000))
console.log('expected: 1 cm, received: ' + fakeBestFit(0.001))
console.log('expected: 1 mi, received: ' + fakeBestFit(1609.34, 'en-US'))
console.log('expected: 1 yd, received: ' + fakeBestFit(0.9143977272588, 'en-US'))