Statements and declarations by category
For an alphabetical listing see the sidebar on the left.
- A block statement is used to group zero or more statements. The block is delimited by a pair of curly brackets.
- Terminates the current loop, switch, or label statement and transfers program control to the statement following the terminated statement.
- Terminates execution of the statements in the current iteration of the current or labeled loop, and continues execution of the loop with the next iteration.
- Executes a statement if a specified condition is true. If the condition is false, another statement can be executed.
- Evaluates an expression, matching the expression's value to a case clause, and executes statements associated with that case.
- Throws a user-defined exception.
- Marks a block of statements to try, and specifies a response, should an exception be thrown.
- Declares a variable, optionally initializing it to a value.
- Declares a block scope local variable, optionally initializing it to a value.
- Declares a read-only named constant.
Functions and classes
- Declares a function with the specified parameters.
- Generators functions enable writing iterators more easily.
- Specifies the value to be returned by a function.
- Declares a class.
- Creates a loop that executes a specified statement until the test condition evaluates to false. The condition is evaluated after executing the statement, resulting in the specified statement executing at least once.
- Creates a loop that consists of three optional expressions, enclosed in parentheses and separated by semicolons, followed by a statement executed in the loop.
- Iterates a specified variable over all values of object's properties. For each distinct property, a specified statement is executed.
- Iterates over the enumerable properties of an object, in arbitrary order. For each distinct property, statements can be executed.
- Iterates over iterable objects (including arrays, array-like objects, iterators and generators), invoking a custom iteration hook with statements to be executed for the value of each distinct property.
- Creates a loop that executes a specified statement as long as the test condition evaluates to true. The condition is evaluated before executing the statement.
- Invokes any available debugging functionality. If no debugging functionality is available, this statement has no effect.
- Used to export functions to make them available for imports in external modules, another scripts.
- Used to import functions exported from an external module, another script.
- Provides a statement with an identifier that you can refer to using a
- Extends the scope chain for a statement.
|ECMAScript 1st Edition.||Standard||Initial definition.|
|ECMAScript 5.1 (ECMA-262)
The definition of 'Statements' in that specification.
|ECMAScript 2015 (6th Edition, ECMA-262)
The definition of 'ECMAScript Language: Statements and Declarations' in that specification.
|Standard||New: function*, let, for...of, yield, class|