EsDay

EsDay is a JavaScript library inspired by Day.js.

EsDay has an API largely similar to Moment.js (v2.30.1) and Day.js (v1.11.13), but it is written in TypeScript and fully supports es modules. When there are differences between Moment.js and Day.js, the functionality of Moment.js is usually preferred.

Core functions

The EsDay core module has many integrated functions. Details see documentation of Core.

Locales

EsDay supports many locales. A list of the supported locales can be found in the details page.

Plugins

EsDay is extensible by plugins. A list of all available plugins can be found in the plugin documentation.

Differences to Day.js

• Locale: Locale is a Plugin; no default locale! Dayjs uses 'en-US' as default.
• 'Start of Week': Default 'Start of Week' is 1 ('Monday') as defined by ISO 8601. Dayjs uses 0 ('Sunday') as (as defined by the dafault locale 'en-US').
• 'Start of Year': Default 'Start of Year' is 4 (Jan 4th must be in the 1st week of the year) as defined by ISO 8601. Dayjs uses 1 (Jan 1st) as (as defined by the dafault locale 'en-US').
• Invalid Date: conforms to Moment.js and uses Invalid date instead of Invalid Date.

Differences to Moment.js

Esday uses moment@2.30.1 as api reference.

• toString: conforms to Day.js and uses Date.toUTCString() (returning the date in RFC 7231 format 'ddd, DD MMM YYYY HH:mm:ss [GMT]') while moment uses the format 'ddd MMM DD YYYY HH:mm:ss [GMT]ZZ'.
• toISOString: conforms to Day.js and returns 'Invalid date' when called on an invalid date. In that case moment returns null (see moment pr#3710).