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The n2 - n1 in the case of a negative number as a result when converted to bool will yield true. So n1 turns out to be less than n2. That's why it is a bad practice to use ints in such Boolean context.

Yes, as stated in the documentation:

...comparison function object which returns ​true if the first argument is less than the second

But the implementation of the comparison here leads to failure. Try this and see for yourself:

Run ‘python manage.py collectstatic’ and try again.

The way you handle static wrong, remove the static dirs in your INSTALLED_APPS out of STATIC_DIRS and set a STATIC_ROOT then collectstatic again.

Add the following as django documentation to your urls.py

The difference in behaviour can be accounted for by this behaviour, described in (for instance) the following note in ECMAScript 2022 Language Specification sect 14.3.2.1:

NOTE: If a VariableDeclaration is nested within a with statement and the BindingIdentifier in the VariableDeclaration is the same as a property name of the binding object of the with statement's object Environment Record, then step 5 will assign value to the property instead of assigning to the VariableEnvironment binding of the Identifier.

In the first case:

The problem is that your CSS selectors include parentheses () and dollar signs $. These symbols already have a special meaning. See:

• () - Are parentheses allowed in CSS selectors?
• $ - [attribute$=value] Selector

You can escape these characters using a backslash \.

Since, I am not 100% sure the context in which you are trying to apply the MVC pattern, a good generic explanation of MVC can be found in GoF's 1995 book, Design Patterns: Elements of Reusable Object Oriented Software.

In the book, they state the following.

The Model is the application object, the View is its screen presentation, and the Controller defines the way the user interface reacts to user input.

A more robust explanation can be found from Martin Fowler where he also makes the case for a variation of Model View Controller that uses a Presentation Model.

If you are referring to Spring MVC then there is some magic that blurs the lines a bit. But in general, you have a controller that represents some screen or an encapsulated piece of functionality that the user (web requests) interact with. The controller serves up responses that are derived from the domain, usually via a Spring Service (i.e. @Service). The domain (Model) doesn't know anything about the View and the View may or may not know anything about the domain.

Given that, the View should be derived from the Model. But that's not always the case since sometimes how we present things to a screen is not the best logical way to model things in our domain - not to mention, the domain should be presentation agnostic. This leads into Fowler's argument for a Presentation Model, which is a model that belongs to the Presentation.

I call this a Presentation Model because it's a model that is really designed for and thus part of the presentation layer.

Microsoft took that idea and ran with it in a variant of MVC called MVVM (Model View ViewModel).

You can read more about that in Microsoft's documentation on ASP.Net Core.

So, back to your original question of "Should you pass the model directly to the view?" If you are using MVC then the controller is what provides the interaction. But if you're really asking, "Can you bind your view directly to the model?" If your model has all the stuff you need organized how your view needs it, then sure. And if it's simple enough, maybe that's the way to go. Otherwise, you could go with something like a Presentation Model or MVVM.

The issue you are having has nothing to do with templates. You cannot invoke std::async() on a member function without binding it to an instance. Wrapping the call in a lambda does the trick.

Here's an example:

You have to initialize all instance properties somehow. And you have to do it right up front, either in the declaration line or in your init method.

But what if you don't actually have the initial value until later, like in viewDidLoad? Then it is silly to supply a real heavyweight value only to replace it later:

Use str.format to replace the {year}.

f-strings are literals and must be an expression. Python will not replace data in string, just because there is a variable of the same name in the bracket notation.

There is a difference between a file and a file descriptor (FD).

All processes share the same files. They don't necessarily have access to the same files, and a file is not its name, either; two different processes which open the same name might not actually open the same file, for example if the first file were renamed or unlinked and a new file were associated with the name. But if they do open the same file, it's necessarily shared, and changes will be mutually visible.

But a file descriptor is not a file. It refers to a file (not a filename, see above), but it also contains other information, including a file position used for and updated by calls to read and write. (You can use "positioned" read and write, pread and pwrite, if you don't want to use the position in the FD.) File descriptors are shared between parent and child processes, and so the file position in the FD is also shared.

Another thing stored in the file descriptor (in the kernel, where user processes can't get at it) is the list of permitted actions (on Unix, read, write, and/or execute, and possibly others). Permissions are stored in the file directory, not in the file itself, and the requested permissions are copied into the file descriptor when the file is opened (if the permissions are available.) It's possible for a child process to have a different user or group than the parent, particularly if the parent is started with augmented permissions but drops them before spawning the child. A file descriptor for a file opened in this manner still has the same permissions uf it is shared with a child, even if the child would itself be able to open the file.