Javascript dates are weird. Famously, Brendan Eich wrote the first version of Javascript in 10 days - and the Date function itself was no exception. It is based on code that was ultimately deprecated ...

In theory, handling dates as a developer is as simple as creating, storing, and, if necessary, manipulating dates. But as a JavaScript developer, you would know this theory doesn’t hold long after you ...

A cron job that worked perfectly for six months suddenly runs two hours early. A payment dashboard shows yesterday's revenue in today's column. Session tokens expire at unpredictable times. These bugs ...

While planning to attend a standards committee meeting in Bergen, Norway in 2023 to discuss Temporal, a proposed replacement for JavaScript’s Date object, developer Philip Chimento of Igalia’s ...

let now = new Date(); // 常に現在時刻を入れておく為のオブジェクト function calc(){ let now = new Date(); // 使い捨てにする計算用。必ず別に定義する。 let people = document.getElementById("people").value; // 入力フォームのvalueを取得 let add_minutes = ...

Webアプリケーションの品質を高める上で、「パフォーマンスの計測」は避けて通れない課題です。 「この処理に何秒かかったのか？」 「ユーザーがページを開いてからどれくらい滞在しているのか？」 こうしたデータを正確に、かつシステムに負荷をかけ ...

OK, you have mastered the way your particular language represents dates and times. But this is just the start. Doing arithmetic with dates can go well beyond just working out the interval between two ...