exits | Run arbitrary functions & commands | Command Line Interface library

The error message is saying it all: "most likely due to a circular import".

pxxtf.py

But is it set to zero?

No / maybe. There are no guarantees about the "value" of unallocated memory. Nor is there any way guaranteed by the standard to observe that hypothetical "value".

From an information security perspective: If you store private information in an object, then you should assume that the information may persist even after the storage duration of the object. And that an attacker may be able to access that information if your program is vulnerable to an exploit (typically, through undefined behaviour).

The $? operator gets the return code of the previously run command. So, you can use it in conjunction with an if statement to verify that npm run build completed successfully.

I would add the celery user to the sudoers file with the only command allowed being the one needed. Use visudo and add these lines

When you run your Go application inside a docker container, the localhost IP 127.0.0.1 is referring to this container. You should use the hostname of your Redis container to connect from your Go container, so your connection string would be:

The thing the compiler is looking for is a lifetime bound. A lifetime bound of 'a doesn't mean “this type is a reference with lifetime 'a”, but rather “all of the references this type contains have lifetimes of at least 'a”.

(When a lifetime bound is written explicitly, it looks like where T: 'a.)

Thus, any type which does not contain any references (or rather, has no lifetime parameters) automatically satisfies the 'static lifetime bound. If T: 'static, then Arc: 'static (and the same for Box and Rc).

How could Arc::clone(&msg) get a 'static lifetime? The value it points to isn't known at compile-time, and could die before the whole program exits.

It does not point to the value using a reference, so it's fine. The type of your value is Arc>; there are no lifetime parameters here because there are no references. If it were, hypothetically, Arc<'a, Mutex> (a lifetime parameter which Arc doesn't actually have), then that type would not satisfy the bound.

The job of Arc (or Rc or Box) is to own the value it points to. Ownership is not a reference and thus not subject to lifetimes.

However, if you had the type Arc<&'a str>> then that would not satisfy the bound, because it contains a reference which is not 'static.

Other than the usual suspects (process.exit(), or process termination/signal, or crash/hardware failure), are there any circumstances where code in a finally block will not be reached?

If the promise will resolve or reject in future then it should reach to the final block.

According to the MDN docs,

The finally-block contains statements to execute after the try-block and catch-block(s) execute, but before the statements following the try...catch...finally-block. Note that the finally-block executes regardless of whether an exception is thrown. Also, if an exception is thrown, the statements in the finally-block execute even if no catch-block handles the exception.

A promise is just a JavaScript object. An object can have many states. A promise object can be in pending state or settled state. The state settled can divide as fulfilled and rejected. For this example just imagine we have only two state as PENDING and SETTLED.

Now if the promise never resolve or reject then it will never go to the settled state which means your then..catch..finally will never call. If nothing is reference to the promise then it will just garbage collected.

In your original question you mentioned about a 3rd party async method. If you see that code, the first thing you can see is, there are set of if(..) blocks to determine the current OS. But it does not have any else block or a default case.

What if non of the if(..) blocks are trigger ? There is nothing to execute and you already returned a promise with return new Promise(). So basically if non of the if(..) blocks are triggered, the promise will never change its state from pending to settled.

And then as @Bergi also mentioned there are some codes like this. A classic Promise constructor antipattern as he mentioned. For example see the below code,

I assume that when you say "If I use parentheses on that line it works", you mean that the following works as expected:

From what I can find online, you should NOT use an eventloop to cause the QAIM to wait in any of its methods.

Instead, return an immediate value with an option 'datavalid' flag which the view should use to present/hide output. Then request data from the remote model, and upon receipt issue the data changed signal for the view to update the data onscreen.