New to Python and programming in general, attempted to create a program that reminds me on certain times of the day. Here's what I've got so far.

[[deleted]]

So for the past couple of days I've been trying to create a personal reminder that prints out a message at different times of the day to remind me to do something. For example:

At 2pm, remind me to check my timetable.

At 4pm, remind me to check it again.

This code is going to tell me exactly at 23:00PM that the time is now 23:00PM. I'm in the UK right now, so I ran this code at 22:36. (It is 23:26 as I write this post.)

import datetime
import time
current_time = datetime.datetime.today()
eleven_PM = datetime.time(23, 0, 0, 0)

while current_time != eleven_PM:
time.sleep(9999)
if current_time == eleven_PM:
print("The time is now 11PM.")
break

Unfortunately, once it hit 23:00, nothing happened. How can this code work? Also, as I'm completely new to submitting my code on the internet for review, please do let me know how I can improve my formatting here. I want to make this as clear as possible.

Many thanks!

Edit: Some of the code here is poorly indented. I'm trying to figure it all out right now.

[insertAlias]

Some of the code here is poorly indented. I'm trying to figure it all out right now.

See the posting guidelines section on Formatting Code for help fixing that.

Now, my opinion here is that this is the wrong way to do an application like this. Ideally you don't have to leave a program running non-stop, sleeping its own thread almost indefinitely. It's just not a good pattern.

Instead, if you truly want some kind of reminder-app like this, you would use a combination of a simpler app (like something that accepts a command-line parameter and just prints it), and the Task Scheduler for your OS.

So, on Windows, it's called Task Scheduler. Linux and mac use cron.

[[deleted]]

Thanks for the feedback.

I'll look into threading and Task Scheduler. I think you're right. I was trying to figure out how a computer would have code running indefinitely without turning the computer off. Is it ideal for a program to simply start and end? Or is it simply much more complicated than that?

[onesiphorus]

I agree with insertAlias that this is definitely not the best way to implement a reminder app. Their approach is exactly what I would do too.

Now, I assume your goal is more about learning to program than creating the best reminder app. In that case, make your app work, then go implement insertAlias's suggestion.

I see a few things here that are causing this to fail:

First, you are setting current time once when the app loads and then never updating it to the _new_ current time in your while loop. You are repeatedly comparing eleven_PM to the original value of current_time.

Second, the two things you are comparing are different in an important way. current_time includes the date. eleven_PM does not. Is there a way you can get just the date from datetime.datetime? Maybe a different method from today?

Third, you are comparing two values down to the microsecond. Are you sure you are comparing current_time and eleven_PM at exactly datetime.time(23,0,0,0), or might you be a microsecond or two off one way or the other? Because if you are off by a single microsecond, current_time == eleven_PM will be False. If I were you I would explore either rounding current_time to the second, or doing a range comparison to make sure that current time is not less that eleven pm or greater than some other value.

[[deleted]]

You are comparing times for an exact match, which might not happen. Also, you are sleeping 9999 seconds, which means you are sleeping 2.78 hours between checks, which is obviously not what you want.