Docs

Docs is a community-driven collection of code documentation for popular programming languages and frameworks. Interested in helping build it? Read the Contribution Guide or share your feedback.

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Arrays

Arrays are lists of ordered, stored data. They can hold items that are of any data type. Arrays are created by using square brackets, with individual elements separated by commas. js // An array containing numbers const numberArray = [0, 1, 2, 3]; // An array containing different data types const mixedArray = [1, chicken, false];

Built-in Functions

The Python interpreter has a set of functions and types built into it (pre-defined). They are always ready at your disposal; you can use them without needing to import a library. There are 68 built-in functions and they are listed here in alphabetical order.

Classes

Classes are templates used to define the properties and methods of objects in code. They can describe the kinds of information that the class holds, and also how a programmer interacts with that data. It serves as a blueprint or template for the objects, or "instances" of the class. In Python, classes are defined using the class keyword. py class Animal: def init(self, name, leg_count): self.name = name

Attributes

HTML attributes can be added to the opening tag of an HTML element to change the elements default behavior or provide additional information about the element. They consist of a name and a value using the following syntax: name="value".

Aggregate Functions

In SQL, aggregate functions perform a calculation on a set of values and return a single value. They are often used with the GROUP BY clause of the SELECT statement. Note: Except for COUNT(), aggregate functions ignore all NULL values. List all the years and their number of movies, but only the years with more than 5 movies: sql SELECT year, COUNT() FROM movies

Casting

Casting is a method that converts a variables data type into another data type.

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Concept of the Week

Ken Thompson

Ken Thompson is an American computer scientist, known for creating many significant works in the field, such as the Unix and Plan 9 operating systems, the B (1969) and Go (2019) programming languages, the grep command line utility, and UTF-8 encoding. Ken Thompson is best known for working alongside Dennis Ritchie and others at Bell Laboratories, where they began working on Unix in 1967 as a replacement operating system for the Digital Equipment Corporations PDP-7 mini computer. During this time, Ken Thompson developed the B programming language, which would become the precursor for the incredibly popular and influential C programming language.

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Closures

Closures allows for more flexible code.

Classes

Protocols

Tuples

Top community contributors

Concept of the Week

Ken Thompson

Ken Thompson is an American computer scientist, known for creating many significant works in the field, such as the Unix and Plan 9 operating systems, the B (1969) and Go (2019) programming languages, the grep command line utility, and UTF-8 encoding. Ken Thompson is best known for working alongside Dennis Ritchie and others at Bell Laboratories, where they began working on Unix in 1967 as a replacement operating system for the Digital Equipment Corporations PDP-7 mini computer. During this time, Ken Thompson developed the B programming language, which would become the precursor for the incredibly popular and influential C programming language.

Recently Added

Closures

Closures allows for more flexible code.

Classes

Protocols

Tuples