@ -1,4 +1,4 @@
//! This module implements the `Keyword` structure, which represents reserved words of T he JavaScript language.
//! This module implements the `Keyword` structure, which represents reserved words of t he JavaScript language.
use std ::{
error ,
@ -21,35 +21,16 @@ use serde::{Deserialize, Serialize};
#[ cfg_attr(feature = " serde-ast " , derive(Serialize, Deserialize)) ]
#[ derive(Clone, Copy, PartialEq, Debug) ]
pub enum Keyword {
/// The `await` operator is used to wait for a [`Promise`][promise]. It can only be used inside an [async function][async-function].
///
/// Syntax: `[rv] = await x;`
///
/// The await expression causes async function execution to pause until a Promise is settled (that is, fulfilled or rejected),
/// and to resume execution of the async function after fulfillment. When resumed, the value of the await expression is that of
/// the fulfilled Promise.
///
/// If the Promise is rejected, the await expression throws the rejected value.
/// The `await` keyword.
///
/// More information:
/// - [ECMAScript reference](https://tc39.es/ecma262/#prod-AwaitExpression)
/// - [MDN documentation][mdn]
///
/// [mdn]: https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Operators/await
/// [promise]: https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Promise
/// [async-function]: https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Statements/async_function
Await ,
/// The break statement terminates the current loop, switch, or label statement and transfers program control to the statement following the terminated statement.
///
/// Syntax: `break [label];`
///
/// `label`(optional):
/// > Identifier associated with the label of the statement. If the statement is not a loop or switch, this is required.
///
/// The break statement includes an optional label that allows the program to break out of a labeled statement.
/// The break statement needs to be nested within the referenced label. The labeled statement can be any block statement;
/// it does not have to be preceded by a loop statement.
/// The `break` keyword.
///
/// More information:
/// - [ECMAScript reference](https://tc39.es/ecma262/#prod-BreakStatement)
@ -58,12 +39,7 @@ pub enum Keyword {
/// [mdn]: https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Statements/break
Break ,
/// The `case` keyword is used to match against an expression in a switch statement.
///
/// Syntax: `case x:`
///
/// If the expression matches, the statements inside the case clause are executed until either the end of the
/// switch statement or a break.
/// The `case` keyword.
///
/// More information:
/// - [ECMAScript reference](https://tc39.es/ecma262/#prod-CaseClause)
@ -72,16 +48,8 @@ pub enum Keyword {
/// [mdn]: https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Statements/switch
Case ,
/// The `catch` keyword is use in `catch`-block contains statements that specify what to do if an exception is thrown in the try-block.
///
/// Syntax: `try { ... } catch(x) { ... }`
///
/// `x`:
/// > An identifier to hold an exception object for the associated `catch`-block.
///
/// If any statement within the try-block (or in a function called from within the try-block) throws an exception,
/// control is immediately shifted to the catch-block. If no exception is thrown in the try-block, the catch-block is skipped.
///
/// The `catch` keyword.
///
/// More information:
/// - [ECMAScript reference](https://tc39.es/ecma262/#prod-Catch)
/// - [MDN documentation][mdn]
@ -89,39 +57,17 @@ pub enum Keyword {
/// [mdn]: https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Statements/try...catch
Catch ,
/// The `class` keyword is used to creates a new class with a given name using prototype-based inheritance.
///
/// Syntax: `class [name [extends otherName]] { /* `[`class body`][class-body]` */ }`
///
/// `name`:
/// > The name of the class.
///
/// `otherName`:
/// > The inherited class name.
/// The `class` keyword.
///
/// You can also define a class using a class expression. But unlike a class expression,
/// a class declaration doesn't allow an existing class to be declared again and will throw a `SyntaxError` if attempted.
///
/// The class body of a class declaration is executed in strict mode. The constructor method is optional.
///
/// More information:
/// - [ECMAScript reference](https://tc39.es/ecma262/#prod-ClassDeclaration)
/// - [MDN documentation][mdn]
///
/// [mdn]: https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Statements/class
/// [class-body]: https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Classes#Class_body_and_method_definitions
Class ,
/// The continue 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.
///
/// Syntax: `continue [label];`
///
/// `label`(optional):
/// > Identifier associated with the label of the statement.
///
/// The continue statement can include an optional label that allows the program to jump to the next iteration of a labeled
/// loop statement instead of the current loop. In this case, the continue statement needs to be nested within this labeled statement.
/// The continue keyword.
///
/// More information:
/// - [ECMAScript reference](https://tc39.es/ecma262/#prod-ContinueStatement)
@ -130,18 +76,7 @@ pub enum Keyword {
/// [mdn]: https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Statements/continue
Continue ,
/// Constants are block-scoped, much like variables defined using the let keyword.
///
/// Syntax: `const name1 = value1 [, name2 = value2 [, ... [, nameN = valueN]]];`
///
/// The const declaration creates a read-only reference to a value.
/// It does not mean the value it holds is immutable—just that the variable identifier cannot be reassigned.
///
/// This constant declaration whose scope can be either global or local to the block in which it is declared.
/// Global constants do not become properties of the window object, unlike var variables.
///
/// An initializer for a constant is required. You must specify its value in the same statement in which it's declared.
/// (This makes sense, given that it can't be changed later.)
/// The `const` keyword.
///
/// More information:
/// - [ECMAScript reference](https://tc39.es/ecma262/#sec-let-and-const-declarations)
@ -150,11 +85,7 @@ pub enum Keyword {
/// [mdn]: https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Statements/const
Const ,
/// The `debugger` statement invokes any available debugging functionality, such as setting a breakpoint.
///
/// Syntax: `debugger;`
///
/// If no debugging functionality is available, this statement has no effect.
/// The `debugger` keyword.
///
/// More information:
/// - [ECMAScript reference](https://tc39.es/ecma262/#sec-debugger-statement)
@ -163,25 +94,7 @@ pub enum Keyword {
/// [mdn]: https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Statements/debugger
Debugger ,
/// The `default` keyword can be used within a switch statement, or with an export statement.
///
/// Syntax **in switch statement**:
/// ```text
/// switch (expression) {
/// case value1:
/// //Statements executed when the result of expression matches value1
/// [break;]
/// default:
/// //Statements executed when none of the values match the value of the expression
/// [break;]
/// }
/// ```
///
/// The default keyword will help in any other case and executes the associated statement.
///
/// Syntax **in export statement**: `export default name;`
///
/// If you want to export a single value or need a fallback value for a module, a default export can be used.
/// The `default` keyword.
///
/// More information:
/// - [ECMAScript reference default clause](https://tc39.es/ecma262/#prod-DefaultClause)
@ -191,15 +104,7 @@ pub enum Keyword {
/// [mdn]: https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Statements/default
Default ,
/// The JavaScript `delete` operator removes a property from an object.
///
/// Syntax: `delete x`
///
/// Unlike what common belief suggests, the `delete` operator has **nothing** to do with directly freeing memory.
/// Memory management is done indirectly via breaking references.
///
/// The delete operator removes a given property from an object. On successful deletion,
/// it will return `true`, else `false` will be returned.
/// The `delete` keyword.
///
/// More information:
/// - [ECMAScript reference](https://tc39.es/ecma262/#sec-delete-operator)
@ -208,24 +113,7 @@ pub enum Keyword {
/// [mdn]: https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Operators/delete
Delete ,
/// The `do` keyword is used in `do...while` statement creates a loop that executes a specified statement
/// until the test condition evaluates to `false`.
///
/// Syntax:
/// ```text
/// do
/// statement
/// while (condition);
/// ```
///
/// `statement`
/// > A statement that is executed at least once and is re-executed each time the condition evaluates to `true`.
///
/// `condition`
/// > An expression evaluated after each pass through the loop. If condition evaluates to true,
/// the statement is re-executed. When condition evaluates to `false`, control passes to the statement following the `do...while`.
///
/// The `do...while` loop iterates at least once and reiterates until the given condition return `false`.
/// The `do` keyword.
///
/// More information:
/// - [ECMAScript reference](https://tc39.es/ecma262/#sec-do-while-statement)
@ -242,41 +130,7 @@ pub enum Keyword {
/// Future reserved keywords.
Enum ,
/// The export statement is used when creating JavaScript modules to export functions, objects, or primitive values from the module.
///
/// Syntax:
/// ```text
/// // Exporting individual features
/// export let name1, name2, …, nameN; // also var, const
/// export let name1 = …, name2 = …, …, nameN; // also var, const
/// export function functionName(){...}
/// export class ClassName {...}
///
/// // Export list
/// export { name1, name2, …, nameN };
///
/// // Renaming exports
/// export { variable1 as name1, variable2 as name2, …, nameN };
///
/// // Exporting destructured assignments with renaming
/// export const { name1, name2: bar } = o;
///
/// // Default exports
/// export default expression;
/// export default function (…) { … } // also class, function*
/// export default function name1(…) { … } // also class, function*
/// export { name1 as default, … };
///
/// // Aggregating modules
/// export * from …; // does not set the default export
/// export * as name1 from …;
/// export { name1, name2, …, nameN } from …;
/// export { import1 as name1, import2 as name2, …, nameN } from …;
/// export { default } from …;
///```
///
/// There are two different types of export, named and default. You can have multiple named exports
/// per module but only one default export.
/// The `export` keyword.
///
/// More information:
/// - [ECMAScript reference](https://tc39.es/ecma262/#sec-exports)
@ -285,13 +139,7 @@ pub enum Keyword {
/// [mdn]: https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Statements/export
Export ,
/// The extends keyword is used in class declarations or class expressions to create a class which is a child of another class.
///
/// Syntax: `class ChildClass extends ParentClass { ... }`
///
/// The extends keyword can be used to subclass custom classes as well as built-in objects.
///
/// The .prototype of the extension must be an Object or null.
/// The `extends` keyword.
///
/// More information:
/// - [ECMAScript reference](https://tc39.es/ecma262/#prod-ClassHeritage)
@ -300,11 +148,7 @@ pub enum Keyword {
/// [mdn]: https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Classes/extends
Extends ,
/// The finally statement lets you execute code, after try and catch, regardless of the result.
///
/// Syntax: `try { ... } [catch( ... ) { ... }] [finally { ... }]`
///
/// The catch and finally statements are both optional, but you need to use one of them (if not both) while using the try statement.
/// The `finally` keyword.
///
/// More information:
/// - [ECMAScript reference](https://tc39.es/ecma262/#prod-Finally)
@ -313,26 +157,7 @@ pub enum Keyword {
/// [mdn]: https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Statements/try...catch
Finally ,
/// The **`for` statement** creates a loop that consists of three optional expressions.
///
/// Syntax:
/// ```text
/// for ([initialization]; [condition]; [final-expression])
/// statement
///
/// ```
/// `initialization`:
/// > An expression (including assignment expressions) or variable declaration evaluated once before the loop begins.
///
/// `condition`:
/// > An expression to be evaluated before each loop iteration. If this expression evaluates to true, statement is executed.
///
/// `final-expression`:
/// > An expression to be evaluated at the end of each loop iteration. This occurs before the next evaluation of condition.
///
/// `statement`:
/// > A statement that is executed as long as the condition evaluates to true. To execute multiple statements within the loop,
/// > use a block statement (`{ ... }`) to group those statements.
/// The `for` keyword.
///
/// More information:
/// - [ECMAScript reference](https://tc39.es/ecma262/#prod-ForDeclaration)
@ -341,29 +166,7 @@ pub enum Keyword {
/// [mdn]: https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Statements/for
For ,
/// The **`function` declaration** (function statement) defines a function with the specified parameters.
///
/// Syntax:
/// ```text
/// function name([param[, param,[..., param]]]) {
/// [statements]
/// }
/// ```
///
/// `name`:
/// > The function name.
///
/// `param`(optional):
/// > The name of an argument to be passed to the function. Maximum number of arguments varies in different engines.
///
/// `statements`(optional):
/// > The statements which comprise the body of the function.
///
/// A function created with a function declaration is a `Function` object and has all the properties, methods and behavior of `Function`.
///
/// A function can also be created using an expression (see function expression).
///
/// By default, functions return undefined. To return any other value, the function must have a return statement that specifies the value to return.
/// The `function` keyword.
///
/// More information:
/// - [ECMAScript reference](https://tc39.es/ecma262/#sec-terms-and-definitions-function)
@ -372,52 +175,16 @@ pub enum Keyword {
/// [mdn]: https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Statements/function
Function ,
/// The **`if` statement** executes a statement if a specified condition is [`truthy`][truthy]. If the condition is [`falsy`][falsy], another statement can be executed.
///
/// Syntax:
/// ```text
/// if (condition)
/// statement1
/// [else
/// statement2]
/// ```
///
/// `condition`:
/// > An [expression][expression] that is considered to be either [`truthy`][truthy] or [`falsy`][falsy].
///
/// `statement1`:
/// > Statement that is executed if condition is truthy. Can be any statement, including further nested if statements.
///
/// `statement2`:
/// > Statement that is executed if condition is [`falsy`][falsy] and the else clause exists. Can be any statement, including block statements and further nested if statements.
///
/// Multiple `if...else` statements can be nested to create an else if clause.
///
/// **Note** that there is no elseif (in one word) keyword in JavaScript.
/// The `if` keyword.
///
/// More information:
/// - [ECMAScript reference](https://tc39.es/ecma262/#prod-IfStatement)
/// - [MDN documentation][mdn]
///
/// [mdn]: https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Statements/if...else
/// [truthy]: https://developer.mozilla.org/en-US/docs/Glossary/truthy
/// [falsy]: https://developer.mozilla.org/en-US/docs/Glossary/falsy
/// [expression]: https://developer.mozilla.org/en-US/docs/Web/JavaScript/Guide/Expressions_and_Operators#Expressions
If ,
/// The **`in` operator** returns `true` if the specified property is in the specified object or its prototype chain.
///
/// Syntax: `prop in object`
///
/// `prop`:
/// > A string or symbol representing a property name or array index (non-symbols will be coerced to strings).
///
/// `object`:
/// > Object to check if it (or its prototype chain) contains the property with specified name (`prop`).
///
/// If you delete a property with the `delete` operator, the `in` operator returns `false` for that property.
///
/// If you set a property to `undefined` but do not delete it, the `in` operator returns true for that property.
/// The `in` keyword.
///
/// More information:
/// - [ECMAScript reference](https://tc39.es/ecma262/#prod-RelationalExpression)
@ -426,20 +193,7 @@ pub enum Keyword {
/// [mdn]: https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Operators/in
In ,
/// The **`instanceof` operator** tests whether the `prototype` property of a constructor appears anywhere in the `prototype` chain of an object.
///
/// Syntax: `object instanceof constructor`
///
/// `object`:
/// > The object to test.
///
/// `constructor`:
/// > Function to test against.
///
/// The **`instanceof` operator** tests the presence of `constructor.prototype` in object's `prototype` chain.
///
/// Note that the value of an `instanceof` test can change based on changes to the `prototype` property of constructors.
/// It can also be changed by changing an object's prototype using `Object.setPrototypeOf`. It is also possible using the non-standard `__proto__` pseudo-property.
/// The `instanceof` keyword.
///
/// More information:
/// - [ECMAScript reference](https://tc39.es/ecma262/#sec-instanceofoperator)
@ -448,41 +202,7 @@ pub enum Keyword {
/// [mdn]: https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Operators/instanceof
InstanceOf ,
/// The static **`import` statement** is used to import bindings which are exported by another module.
///
/// Syntax:
/// ```text
/// import defaultExport from "module-name";
/// import * as name from "module-name";
/// import { export1 } from "module-name";
/// import { export1 as alias1 } from "module-name";
/// import { export1 , export2 } from "module-name";
/// import { foo , bar } from "module-name/path/to/specific/un-exported/file";
/// import { export1 , export2 as alias2 , [...] } from "module-name";
/// import defaultExport, { export1 [ , [...] ] } from "module-name";
/// import defaultExport, * as name from "module-name";
/// import "module-name";
/// var promise = import("module-name");
/// ```
///
/// `defaultExport`:
/// > Name that will refer to the default export from the module.
///
/// `module-name`:
/// > The module to import from. This is often a relative or absolute path name to the .js file containing the module.
/// > Certain bundlers may permit or require the use of the extension; check your environment. Only single quoted and double quoted Strings are allowed.
///
/// `name`:
/// > Name of the module object that will be used as a kind of namespace when referring to the imports.
///
/// `exportN`:
/// > Name of the exports to be imported.
///
/// `aliasN`:
/// > Names that will refer to the named imports.
///
/// The `name` parameter is the name of the "module object" which will be used as a kind of namespace to refer to the exports.
/// The `export` parameters specify individual named exports, while the `import * as name` syntax imports all of them.
/// The`import` keyword.
///
/// More information:
/// - [ECMAScript reference](https://tc39.es/ecma262/#sec-imports)
@ -491,33 +211,130 @@ pub enum Keyword {
/// [mdn]: https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Statements/import
Import ,
/// The `let` keyword
/// The `let` keyword.
///
/// More information:
/// - [ECMAScript reference](https://tc39.es/ecma262/#sec-let-and-const-declarations)
/// - [MDN documentation][mdn]
///
/// [mdn]: https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Statements/let
Let ,
/// The `new` keyword
/// The `new` keyword.
///
/// More information:
/// - [ECMAScript reference](https://tc39.es/ecma262/#prod-NewExpression)
/// - [MDN documentation][mdn]
///
/// [mdn]: https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Operators/new
New ,
/// The `return` keyword
///
/// More information:
/// - [ECMAScript reference](https://tc39.es/ecma262/#prod-ReturnStatement)
/// - [MDN documentation][mdn]
///
/// [mdn]: https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Statements/return
Return ,
/// The `super` keyword
///
/// More information:
/// - [ECMAScript reference](https://tc39.es/ecma262/#sec-super-keyword)
/// - [MDN documentation][mdn]
///
/// [mdn]: https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Operators/super
Super ,
/// The `switch` keyword
/// The `switch` keyword.
///
/// More information:
/// - [ECMAScript reference](https://tc39.es/ecma262/#prod-SwitchStatement)
/// - [MDN documentation][mdn]
///
/// [mdn]: https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Statements/switch
Switch ,
/// The `this` keyword
/// The `this` keyword.
///
/// More information:
/// - [ECMAScript reference](https://tc39.es/ecma262/#sec-this-keyword)
/// - [MDN documentation][mdn]
///
/// [mdn]: https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Operators/this
This ,
/// The `throw` keyword
/// The `throw` keyword.
///
/// More information:
/// - [ECMAScript reference](https://tc39.es/ecma262/#prod-ArrowFunction)
/// - [MDN documentation][mdn]
///
/// [mdn]: https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Functions/Arrow_functions
Throw ,
/// The `try` keyword
/// The `try` keyword.
///
/// More information:
/// - [ECMAScript reference](https://tc39.es/ecma262/#prod-TryStatement)
/// - [MDN documentation][mdn]
///
/// [mdn]: https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Statements/try...catch
Try ,
/// The `typeof` keyword
/// The `typeof` keyword.
///
/// More information:
/// - [ECMAScript reference](https://tc39.es/ecma262/#sec-typeof-operator)
/// - [MDN documentation][mdn]
///
/// [mdn]: https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Operators/typeof
TypeOf ,
/// The `var` keyword
/// The `var` keyword.
///
/// More information:
/// - [ECMAScript reference](https://tc39.es/ecma262/#prod-VariableStatement)
/// - [MDN documentation][mdn]
///
/// [mdn]: https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Statements/var
Var ,
/// The `void` keyword
/// The `void` keyword.
///
/// More information:
/// - [ECMAScript reference](https://tc39.es/ecma262/#sec-void-operator)
/// - [MDN documentation][mdn]
///
/// [mdn]: https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Operators/void
Void ,
/// The `while` keyword
/// The `while` keyword.
///
/// More information:
/// - [ECMAScript reference](https://tc39.es/ecma262/#prod-grammar-notation-WhileStatement)
/// - [MDN documentation][mdn]
///
/// [mdn]: https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Statements/while
While ,
/// The `with` keyword
/// The `with` keyword.
///
/// More information:
/// - [ECMAScript reference](https://tc39.es/ecma262/#prod-WithStatement)
/// - [MDN documentation][mdn]
///
/// [mdn]: https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Statements/with
With ,
/// The 'yield' keyword
/// The 'yield' keyword.
///
/// More information:
/// - [ECMAScript reference](https://tc39.es/ecma262/#prod-YieldExpression)
/// - [MDN documentation][mdn]
///
/// [mdn]: https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Operators/yield
Yield ,
}