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Date comparison in TypeScript optimization guide as expected with time zones

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typescript date timezone javascript TypeScript

I'm collaborating on a project where I'm trying to implement Does anyone know how to I'm sure I'm missing something obvious here, but I'm sure I'm missing something obvious here, but I'm experiencing an scenario when comparing date strings in TypeScript, and the results seem inconsistent due to time zone differences. I have a list of event dates stored as ISO strings, and I need to filter out events that are happening after the current date in the user's local time zone. Here’s a simplified version of my code: ```typescript const events: string[] = [ '2023-10-20T12:00:00Z', '2023-10-22T09:00:00Z', '2023-10-21T16:00:00Z' ]; const currentDate = new Date(); const upcomingEvents = events.filter(event => { const eventDate = new Date(event); return eventDate > currentDate; }); console.log(upcomingEvents); ``` When I run this code, it seems to filter out events that I should see. For instance, if today is October 20, 2023, I expect to see events on October 21 and 22, but it returns an empty array sometimes. I've tried using `eventDate.getTime()` for comparison instead of direct comparison, but I still face inconsistencies, especially when testing across different time zones. The scenario seems particularly pronounced when the dates are close to midnight. I’m currently using TypeScript version 4.5.4. Is there something specific I’m missing about how JavaScript handles date comparisons, especially with UTC and local time zones? Are there any best practices I should follow when dealing with dates in a TypeScript application to avoid this kind of confusion? I'm working on a service that needs to handle this. Is there a better approach? Is there a better approach? For context: I'm using Typescript on Debian. Has anyone else encountered this? This is happening in both development and production on Windows 10. This issue appeared after updating to Typescript 3.10. I'm working on a REST API that needs to handle this. Any ideas what could be causing this?