date format
Updated on September 27, 2024Source codeTests
createDateFormat is a pipe that transforms a date or timestamp (number) to a string formatted by Intl.DateTimeFormat.
Create format
Call createDateFormat with the Intl.DateTimeFormat constructor's parameters to create your format function.
Creating new Intl instances can be expensive, so createDateFormat implements some performance improvements:
- Each time you call
createDateFormat, it checks to see if you have already created aDateTimeFormatinstance with the same parameters. If you have, it reuses that instance. - Each time you call your
formatfunction, it reuses the sameDateTimeFormatinstance.
import { createDateFormat as createFormat } from '@baleada/logic'
// The first time you call `createFormat`, it creates a new
// `DateTimeFormat` instance, and returns the `format` function.
const format = createFormat(
'en',
{
weekday: 'long',
year: 'numeric',
month: 'long',
day: 'numeric',
}
)
format(new Date()) // 'Tuesday, August 20, 2024'
// In a distant part of your app, you might call `createFormat`
// again with the same parameters. `createFormat` will check for
// deep equality between the parameters you pass and any parameters
// that have been passed before.
//
// In this case, parameters are deeply equal, so `createFormat`
// will internally reuse the original `DateTimeFormat` instance,
// boosting your app's performance:
const formatAgain = createFormat(
'en',
{
weekday: 'long',
year: 'numeric',
month: 'long',
day: 'numeric',
}
)
formatAgain(new Date()) // 'Tuesday, August 20, 2024'
