Regular expressions are patterns used to match character combinations in strings. In JavaScript, regular expressions are also objects. These patterns are used with the exec() and test() methods of RegExp, and with the match(), matchAll(), replace(), replaceAll(), search(), and split() methods of String. This chapter describes JavaScript regular expressions. It provides a brief overview of each syntax element. For a detailed explanation of each one's semantics, read the regular expressions reference.

The conditional (ternary) operator is the only JavaScript operator that takes three operands: a condition followed by a question mark (?), then an expression to execute if the condition is truthy followed by a colon (:), and finally the expression to execute if the condition is falsy. This operator is frequently used as an alternative to an if...else statement.

The divisor attribute specifies the value by which the resulting number of applying the kernelMatrix of a <feConvolveMatrix> element to the input image color value is divided to yield the destination color value.

The dy attribute indicates a shift along the y-axis on the position of an element or its content.

Assigns a class name or set of class names to an element. You may assign the same class name or names to any number of elements, however, multiple class names must be separated by whitespace characters.

The eval() function evaluates JavaScript code represented as a string and returns its completion value. The source is parsed as a script.

The <set> SVG element provides a method of setting the value of an attribute for a specified duration.

The InternalError object indicates an error that occurred internally in the JavaScript engine.

Visual Studio Code's integrated terminal allows customizing its appearance in various ways.

Use smart actions in VS Code to get help from AI for common development tasks, such as generating commit messages, renaming symbols, or fixing coding errors.