In this case, there are some benefits to allowing this: 1) Methods are just functions that happen defined in a class, and need to be callable either as bound methods with implicit self passing or as plain functions with explicit self passing. 2) Making classmethod s and staticmethod s means you want to be able to rename and omit self respectively.
For a language-agnostic consideration of the design decision, see What is the advantage of having this/self pointer mandatory explicit?. To close debugging questions where OP omitted a self parameter for a method and got a TypeError, use TypeError: method () takes 1 positional argument but 2 were given instead. If OP omitted self. in the body of the method and got a NameError, consider How can ...
A self join is a join of a table with itself. A common use case is when the table stores entities (records) which have a hierarchical relationship between them.
A self join is simply when you join a table with itself. There is no SELF JOIN keyword, you just write an ordinary join where both tables involved in the join are the same table. One thing to notice is that when you are self joining it is necessary to use an alias for the table otherwise the table name would be ambiguous. It is useful when you want to correlate pairs of rows from the same ...
Say I want to implement a method that pretty prints the struct to stdout, should I take &self? I guess self also works? As you can see, this is exactly a case for &self. If you use self (or &mut self) the method will likely still compile, but it can only be used in more restricted situations.
17 What is self? In Python, every normal method is forced to accept a parameter commonly named self. This is an instance of class - an object. This is how Python methods interact with a class's state. You are allowed to rename this parameter whatever you please. but it will always have the same value:
Moving further: Technically both self and this are used for the same thing. They are used to access the variable associated with the current instance. Only difference is, you have to include self explicitly as first parameter to an instance method in Python, whereas this is not the case with Java. Moreover, the name self can be anything.
I am new to Swift and I'm wondering what self is used for and why. I have seen it in classes and structures but I really don't find them essential nor necessary to even mention them in my code. Wh...
9 First, Python's self is not a keyword, it's a coding convention, the same as Python's cls. Guido has written a really detailed and valuable article about the origin of Python's support for class, and in that article, Guido explains why use self and cls, and why they are necessary.
