--- description: 'Require a consistent member declaration order.' --- > 🛑 This file is source code, not the primary documentation location! 🛑 > > See **https://typescript-eslint.io/rules/member-ordering** for documentation. This rule aims to standardize the way classes, interfaces, and type literals are structured and ordered. A consistent ordering of fields, methods and constructors can make code easier to read, navigate, and edit. ## Options ```ts interface Options { default?: OrderConfig; classes?: OrderConfig; classExpressions?: OrderConfig; interfaces?: OrderConfig; typeLiterals?: OrderConfig; } type OrderConfig = MemberType[] | SortedOrderConfig | 'never'; interface SortedOrderConfig { memberTypes?: MemberType[] | 'never'; optionalityOrder?: 'optional-first' | 'required-first'; order: | 'alphabetically' | 'alphabetically-case-insensitive' | 'as-written' | 'natural' | 'natural-case-insensitive'; } // See below for the more specific MemberType strings type MemberType = string | string[]; ``` You can configure `OrderConfig` options for: - **`default`**: all constructs (used as a fallback) - **`classes`**?: override ordering specifically for classes - **`classExpressions`**?: override ordering specifically for class expressions - **`interfaces`**?: override ordering specifically for interfaces - **`typeLiterals`**?: override ordering specifically for type literals The `OrderConfig` settings for each kind of construct may configure sorting on up to three levels: - **`memberTypes`**: organizing on member type groups such as methods vs. properties - **`optionalityOrder`**: whether to put all optional members first or all required members first - **`order`**: organizing based on member names, such as alphabetically ### Groups You can define many different groups based on different attributes of members. The supported member attributes are, in order: - **Accessibility** (`'public' | 'protected' | 'private' | '#private'`) - **Decoration** (`'decorated'`): Whether the member has an explicit accessibility decorator - **Kind** (`'call-signature' | 'constructor' | 'field' | 'readonly-field' | 'get' | 'method' | 'set' | 'signature' | 'readonly-signature'`) Member attributes may be joined with a `'-'` to combine into more specific groups. For example, `'public-field'` would come before `'private-field'`. ### Orders The `order` value specifies what order members should be within a group. It defaults to `as-written`, meaning any order is fine. Other allowed values are: - `alphabetically`: Sorted in a-z alphabetical order, directly using string `<` comparison (so `B` comes before `a`) - `alphabetically-case-insensitive`: Sorted in a-z alphabetical order, ignoring case (so `a` comes before `B`) - `natural`: Same as `alphabetically`, but using [`natural-compare-lite`](https://github.com/litejs/natural-compare-lite) for more friendly sorting of numbers - `natural-case-insensitive`: Same as `alphabetically-case-insensitive`, but using [`natural-compare-lite`](https://github.com/litejs/natural-compare-lite) for more friendly sorting of numbers ### Default configuration The default configuration looks as follows: ```jsonc { "default": [ // Index signature "signature", "call-signature", // Fields "public-static-field", "protected-static-field", "private-static-field", "#private-static-field", "public-decorated-field", "protected-decorated-field", "private-decorated-field", "public-instance-field", "protected-instance-field", "private-instance-field", "#private-instance-field", "public-abstract-field", "protected-abstract-field", "public-field", "protected-field", "private-field", "#private-field", "static-field", "instance-field", "abstract-field", "decorated-field", "field", // Static initialization "static-initialization", // Constructors "public-constructor", "protected-constructor", "private-constructor", "constructor", // Getters "public-static-get", "protected-static-get", "private-static-get", "#private-static-get", "public-decorated-get", "protected-decorated-get", "private-decorated-get", "public-instance-get", "protected-instance-get", "private-instance-get", "#private-instance-get", "public-abstract-get", "protected-abstract-get", "public-get", "protected-get", "private-get", "#private-get", "static-get", "instance-get", "abstract-get", "decorated-get", "get", // Setters "public-static-set", "protected-static-set", "private-static-set", "#private-static-set", "public-decorated-set", "protected-decorated-set", "private-decorated-set", "public-instance-set", "protected-instance-set", "private-instance-set", "#private-instance-set", "public-abstract-set", "protected-abstract-set", "public-set", "protected-set", "private-set", "#private-set", "static-set", "instance-set", "abstract-set", "decorated-set", "set", // Methods "public-static-method", "protected-static-method", "private-static-method", "#private-static-method", "public-decorated-method", "protected-decorated-method", "private-decorated-method", "public-instance-method", "protected-instance-method", "private-instance-method", "#private-instance-method", "public-abstract-method", "protected-abstract-method", "public-method", "protected-method", "private-method", "#private-method", "static-method", "instance-method", "abstract-method", "decorated-method", "method" ] } ``` :::note The default configuration contains member group types which contain other member types. This is intentional to provide better error messages. ::: :::tip By default, the members are not sorted. If you want to sort them alphabetically, you have to provide a custom configuration. ::: ## Examples ### General Order on All Constructs This config specifies the order for all constructs. It ignores member types other than signatures, methods, constructors, and fields. It also ignores accessibility and scope. ```jsonc // .eslintrc.json { "rules": { "@typescript-eslint/member-ordering": [ "error", { "default": ["signature", "method", "constructor", "field"] } ] } } ``` #### ❌ Incorrect ```ts interface Foo { B: string; // -> field new (); // -> constructor A(): void; // -> method [Z: string]: any; // -> signature } ``` ```ts type Foo = { B: string; // -> field // no constructor A(): void; // -> method // no signature }; ``` ```ts class Foo { private C: string; // -> field public D: string; // -> field protected static E: string; // -> field constructor() {} // -> constructor public static A(): void {} // -> method public B(): void {} // -> method [Z: string]: any; // -> signature } ``` ```ts const Foo = class { private C: string; // -> field public D: string; // -> field constructor() {} // -> constructor public static A(): void {} // -> method public B(): void {} // -> method [Z: string]: any; // -> signature protected static E: string; // -> field }; ``` #### ✅ Correct ```ts interface Foo { [Z: string]: any; // -> signature A(): void; // -> method new (); // -> constructor B: string; // -> field } ``` ```ts type Foo = { // no signature A(): void; // -> method // no constructor B: string; // -> field }; ``` ```ts class Foo { [Z: string]: any; // -> signature public static A(): void {} // -> method public B(): void {} // -> method constructor() {} // -> constructor private C: string; // -> field public D: string; // -> field protected static E: string; // -> field } ``` ```ts const Foo = class { [Z: string]: any; // -> signature public static A(): void {} // -> method public B(): void {} // -> method constructor() {} // -> constructor private C: string; // -> field public D: string; // -> field protected static E: string; // -> field }; ``` ### Classes #### Public Instance Methods Before Public Static Fields This config specifies that public instance methods should come first before public static fields. Everything else can be placed anywhere. It doesn't apply to interfaces or type literals as accessibility and scope are not part of them. ```jsonc // .eslintrc.json { "rules": { "@typescript-eslint/member-ordering": [ "error", { "default": ["public-instance-method", "public-static-field"] } ] } } ``` ##### ❌ Incorrect ```ts class Foo { private C: string; // (irrelevant) public D: string; // (irrelevant) public static E: string; // -> public static field constructor() {} // (irrelevant) public static A(): void {} // (irrelevant) [Z: string]: any; // (irrelevant) public B(): void {} // -> public instance method } ``` ```ts const Foo = class { private C: string; // (irrelevant) [Z: string]: any; // (irrelevant) public static E: string; // -> public static field public D: string; // (irrelevant) constructor() {} // (irrelevant) public static A(): void {} // (irrelevant) public B(): void {} // -> public instance method }; ``` ##### ✅ Correct ```ts class Foo { public B(): void {} // -> public instance method private C: string; // (irrelevant) public D: string; // (irrelevant) public static E: string; // -> public static field constructor() {} // (irrelevant) public static A(): void {} // (irrelevant) [Z: string]: any; // (irrelevant) } ``` ```ts const Foo = class { public B(): void {} // -> public instance method private C: string; // (irrelevant) [Z: string]: any; // (irrelevant) public D: string; // (irrelevant) constructor() {} // (irrelevant) public static A(): void {} // (irrelevant) public static E: string; // -> public static field }; ``` #### Static Fields Before Instance Fields This config specifies that static fields should come before instance fields, with public static fields first. It doesn't apply to interfaces or type literals as accessibility and scope are not part of them. ```jsonc { "rules": { "@typescript-eslint/member-ordering": [ "error", { "default": ["public-static-field", "static-field", "instance-field"] } ] } } ``` ##### ❌ Incorrect ```ts class Foo { private E: string; // -> instance field private static B: string; // -> static field protected static C: string; // -> static field private static D: string; // -> static field public static A: string; // -> public static field [Z: string]: any; // (irrelevant) } ``` ```ts const foo = class { public T(): void {} // method (irrelevant) private static B: string; // -> static field constructor() {} // constructor (irrelevant) private E: string; // -> instance field protected static C: string; // -> static field private static D: string; // -> static field [Z: string]: any; // signature (irrelevant) public static A: string; // -> public static field }; ``` ##### ✅ Correct ```ts class Foo { public static A: string; // -> public static field private static B: string; // -> static field protected static C: string; // -> static field private static D: string; // -> static field private E: string; // -> instance field [Z: string]: any; // (irrelevant) } ``` ```ts const foo = class { [Z: string]: any; // -> signature (irrelevant) public static A: string; // -> public static field constructor() {} // -> constructor (irrelevant) private static B: string; // -> static field protected static C: string; // -> static field private static D: string; // -> static field private E: string; // -> instance field public T(): void {} // -> method (irrelevant) }; ``` #### Class Declarations This config only specifies an order for classes: methods, then the constructor, then fields. It does not apply to class expressions (use `classExpressions` for them). Default settings will be used for class declarations and all other syntax constructs other than class declarations. ```jsonc // .eslintrc.json { "rules": { "@typescript-eslint/member-ordering": [ "error", { "classes": ["method", "constructor", "field"] } ] } } ``` ##### ❌ Incorrect ```ts class Foo { private C: string; // -> field public D: string; // -> field protected static E: string; // -> field constructor() {} // -> constructor public static A(): void {} // -> method public B(): void {} // -> method } ``` ##### ✅ Correct ```ts class Foo { public static A(): void {} // -> method public B(): void {} // -> method constructor() {} // -> constructor private C: string; // -> field public D: string; // -> field protected static E: string; // -> field } ``` #### Class Expressions This config only specifies an order for classes expressions: methods, then the constructor, then fields. It does not apply to class declarations (use `classes` for them). Default settings will be used for class declarations and all other syntax constructs other than class expressions. ```jsonc // .eslintrc.json { "rules": { "@typescript-eslint/member-ordering": [ "error", { "classExpressions": ["method", "constructor", "field"] } ] } } ``` ##### ❌ Incorrect ```ts const foo = class { private C: string; // -> field public D: string; // -> field protected static E: string; // -> field constructor() {} // -> constructor public static A(): void {} // -> method public B(): void {} // -> method }; ``` ##### ✅ Correct ```ts const foo = class { public static A(): void {} // -> method public B(): void {} // -> method constructor() {} // -> constructor private C: string; // -> field public D: string; // -> field protected static E: string; // -> field }; ``` ### Interfaces This config only specifies an order for interfaces: signatures, then methods, then constructors, then fields. It does not apply to type literals (use `typeLiterals` for them). Default settings will be used for type literals and all other syntax constructs other than class expressions. :::note These member types are the only ones allowed for `interfaces`. ::: ```jsonc // .eslintrc.json { "rules": { "@typescript-eslint/member-ordering": [ "error", { "interfaces": ["signature", "method", "constructor", "field"] } ] } } ``` #### ❌ Incorrect ```ts interface Foo { B: string; // -> field new (); // -> constructor A(): void; // -> method [Z: string]: any; // -> signature } ``` #### ✅ Correct ```ts interface Foo { [Z: string]: any; // -> signature A(): void; // -> method new (); // -> constructor B: string; // -> field } ``` ### Type Literals This config only specifies an order for type literals: signatures, then methods, then constructors, then fields. It does not apply to interfaces (use `interfaces` for them). Default settings will be used for interfaces and all other syntax constructs other than class expressions. :::note These member types are the only ones allowed for `typeLiterals`. ::: ```jsonc // .eslintrc.json { "rules": { "@typescript-eslint/member-ordering": [ "error", { "typeLiterals": ["signature", "method", "constructor", "field"] } ] } } ``` #### ❌ Incorrect ```ts type Foo = { B: string; // -> field A(): void; // -> method new (); // -> constructor [Z: string]: any; // -> signature }; ``` #### ✅ Correct ```ts type Foo = { [Z: string]: any; // -> signature A(): void; // -> method new (); // -> constructor B: string; // -> field }; ``` ### Sorting Options #### Sorting Alphabetically Within Member Groups This config specifies that within each `memberTypes` group, members are in an alphabetic case-sensitive order. You can copy and paste the default order from [Default Configuration](#default-configuration). ```jsonc // .eslintrc.json { "rules": { "@typescript-eslint/member-ordering": [ "error", { "default": { "memberTypes": [ /* */ ], "order": "alphabetically" } } ] } } ``` ##### ❌ Incorrect ```ts interface Foo { a: x; B: x; c: x; B(): void; c(): void; a(): void; } ``` ##### ✅ Correct ```ts interface Foo { B: x; a: x; c: x; B(): void; a(): void; c(): void; } ``` #### Sorting Alphabetically Case Insensitive Within Member Groups This config specifies that within each `memberTypes` group, members are in an alphabetic case-sensitive order. You can copy and paste the default order from [Default Configuration](#default-configuration). ```jsonc // .eslintrc.json { "rules": { "@typescript-eslint/member-ordering": [ "error", { "default": { "memberTypes": [ /* */ ], "order": "alphabetically-case-insensitive" } } ] } } ``` ##### ❌ Incorrect ```ts interface Foo { B: x; a: x; c: x; B(): void; c(): void; a(): void; } ``` ##### ✅ Correct ```ts interface Foo { a: x; B: x; c: x; a(): void; B(): void; c(): void; } ``` #### Sorting Alphabetically Ignoring Member Groups This config specifies that members are all sorted in an alphabetic case-sensitive order. It ignores any member group types completely by specifying `"never"` for `memberTypes`. ```jsonc // .eslintrc.json { "rules": { "@typescript-eslint/member-ordering": [ "error", { "default": { "memberTypes": "never", "order": "alphabetically" } } ] } } ``` ##### ❌ Incorrect ```ts interface Foo { static c = 0; b(): void; a: boolean; [a: string]: number; // Order doesn't matter (no sortable identifier) new (): Bar; // Order doesn't matter (no sortable identifier) (): Baz; // Order doesn't matter (no sortable identifier) } ``` ##### ✅ Correct ```ts interface Foo { a: boolean; b(): void; static c = 0; [a: string]: number; // Order doesn't matter (no sortable identifier) new (): Bar; // Order doesn't matter (no sortable identifier) (): Baz; // Order doesn't matter (no sortable identifier) } ``` #### Sorting Optional Members First or Last The `optionalityOrder` option may be enabled to place all optional members in a group at the beginning or end of that group. This config places all optional members before all required members: ```jsonc // .eslintrc.json { "rules": { "@typescript-eslint/member-ordering": [ "error", { "default": { "optionalityOrder": "optional-first", "order": "alphabetically" } } ] } } ``` ##### ❌ Incorrect ```ts interface Foo { a: boolean; b?: number; c: string; } ``` ##### ✅ Correct ```ts interface Foo { b?: number; a: boolean; c: string; } ``` This config places all required members before all optional members: ```jsonc // .eslintrc.json { "rules": { "@typescript-eslint/member-ordering": [ "error", { "default": { "optionalityOrder": "required-first", "order": "alphabetically" } } ] } } ``` ##### ❌ Incorrect ```ts interface Foo { a: boolean; b?: number; c: string; } ``` ##### ✅ Correct ```ts interface Foo { a: boolean; c: string; b?: number; } ``` ## All Supported Options ### Member Types (Granular Form) There are multiple ways to specify the member types. The most explicit and granular form is the following: ```jsonc [ // Index signature "signature", "readonly-signature", // Fields "public-static-field", "public-static-readonly-field", "protected-static-field", "protected-static-readonly-field", "private-static-field", "private-static-readonly-field", "#private-static-field", "#private-static-readonly-field", "public-decorated-field", "public-decorated-readonly-field", "protected-decorated-field", "protected-decorated-readonly-field", "private-decorated-field", "private-decorated-readonly-field", "public-instance-field", "public-instance-readonly-field", "protected-instance-field", "protected-instance-readonly-field", "private-instance-field", "private-instance-readonly-field", "#private-instance-field", "#private-instance-readonly-field", "public-abstract-field", "public-abstract-readonly-field", "protected-abstract-field", "protected-abstract-readonly-field", "public-field", "public-readonly-field", "protected-field", "protected-readonly-field", "private-field", "private-readonly-field" "#private-field", "#private-readonly-field" "static-field", "static-readonly-field", "instance-field", "instance-readonly-field" "abstract-field", "abstract-readonly-field", "decorated-field", "decorated-readonly-field", "field", "readonly-field", // Static initialization "static-initialization", // Constructors "public-constructor", "protected-constructor", "private-constructor", // Getters "public-static-get", "protected-static-get", "private-static-get", "#private-static-get", "public-decorated-get", "protected-decorated-get", "private-decorated-get", "public-instance-get", "protected-instance-get", "private-instance-get", "#private-instance-get", "public-abstract-get", "protected-abstract-get", "public-get", "protected-get", "private-get", "#private-get", "static-get", "instance-get", "abstract-get", "decorated-get", "get", // Setters "public-static-set", "protected-static-set", "private-static-set", "#private-static-set", "public-decorated-set", "protected-decorated-set", "private-decorated-set", "public-instance-set", "protected-instance-set", "private-instance-set", "#private-instance-set", "public-abstract-set", "protected-abstract-set", "public-set", "protected-set", "private-set", "static-set", "instance-set", "abstract-set", "decorated-set", "set", // Methods "public-static-method", "protected-static-method", "private-static-method", "#private-static-method", "public-decorated-method", "protected-decorated-method", "private-decorated-method", "public-instance-method", "protected-instance-method", "private-instance-method", "#private-instance-method", "public-abstract-method", "protected-abstract-method" ] ``` :::note If you only specify some of the possible types, the non-specified ones can have any particular order. This means that they can be placed before, within or after the specified types and the linter won't complain about it. ::: ### Member Group Types (With Accessibility, Ignoring Scope) It is also possible to group member types by their accessibility (`static`, `instance`, `abstract`), ignoring their scope. ```jsonc [ // Index signature // No accessibility for index signature. // Fields "public-field", // = ["public-static-field", "public-instance-field"] "protected-field", // = ["protected-static-field", "protected-instance-field"] "private-field", // = ["private-static-field", "private-instance-field"] // Static initialization // No accessibility for static initialization. // Constructors // Only the accessibility of constructors is configurable. See below. // Getters "public-get", // = ["public-static-get", "public-instance-get"] "protected-get", // = ["protected-static-get", "protected-instance-get"] "private-get", // = ["private-static-get", "private-instance-get"] // Setters "public-set", // = ["public-static-set", "public-instance-set"] "protected-set", // = ["protected-static-set", "protected-instance-set"] "private-set", // = ["private-static-set", "private-instance-set"] // Methods "public-method", // = ["public-static-method", "public-instance-method"] "protected-method", // = ["protected-static-method", "protected-instance-method"] "private-method" // = ["private-static-method", "private-instance-method"] ] ``` ### Member Group Types (With Accessibility and a Decorator) It is also possible to group methods or fields with a decorator separately, optionally specifying their accessibility. ```jsonc [ // Index signature // No decorators for index signature. // Fields "public-decorated-field", "protected-decorated-field", "private-decorated-field", "decorated-field", // = ["public-decorated-field", "protected-decorated-field", "private-decorated-field"] // Static initialization // No decorators for static initialization. // Constructors // There are no decorators for constructors. // Getters "public-decorated-get", "protected-decorated-get", "private-decorated-get", "decorated-get", // = ["public-decorated-get", "protected-decorated-get", "private-decorated-get"] // Setters "public-decorated-set", "protected-decorated-set", "private-decorated-set", "decorated-set", // = ["public-decorated-set", "protected-decorated-set", "private-decorated-set"] // Methods "public-decorated-method", "protected-decorated-method", "private-decorated-method", "decorated-method" // = ["public-decorated-method", "protected-decorated-method", "private-decorated-method"] ] ``` ### Member Group Types (With Scope, Ignoring Accessibility) Another option is to group the member types by their scope (`public`, `protected`, `private`), ignoring their accessibility. ```jsonc [ // Index signature // No scope for index signature. // Fields "static-field", // = ["public-static-field", "protected-static-field", "private-static-field"] "instance-field", // = ["public-instance-field", "protected-instance-field", "private-instance-field"] "abstract-field", // = ["public-abstract-field", "protected-abstract-field"] // Static initialization // No scope for static initialization. // Constructors "constructor", // = ["public-constructor", "protected-constructor", "private-constructor"] // Getters "static-get", // = ["public-static-get", "protected-static-get", "private-static-get"] "instance-get", // = ["public-instance-get", "protected-instance-get", "private-instance-get"] "abstract-get", // = ["public-abstract-get", "protected-abstract-get"] // Setters "static-set", // = ["public-static-set", "protected-static-set", "private-static-set"] "instance-set", // = ["public-instance-set", "protected-instance-set", "private-instance-set"] "abstract-set", // = ["public-abstract-set", "protected-abstract-set"] // Methods "static-method", // = ["public-static-method", "protected-static-method", "private-static-method"] "instance-method", // = ["public-instance-method", "protected-instance-method", "private-instance-method"] "abstract-method" // = ["public-abstract-method", "protected-abstract-method"] ] ``` ### Member Group Types (With Scope and Accessibility) The third grouping option is to ignore both scope and accessibility. ```jsonc [ // Index signature // No grouping for index signature. // Fields "field", // = ["public-static-field", "protected-static-field", "private-static-field", "public-instance-field", "protected-instance-field", "private-instance-field", // "public-abstract-field", "protected-abstract-field"] // Static initialization // No grouping for static initialization. // Constructors // Only the accessibility of constructors is configurable. // Getters "get", // = ["public-static-get", "protected-static-get", "private-static-get", "public-instance-get", "protected-instance-get", "private-instance-get", // "public-abstract-get", "protected-abstract-get"] // Setters "set", // = ["public-static-set", "protected-static-set", "private-static-set", "public-instance-set", "protected-instance-set", "private-instance-set", // "public-abstract-set", "protected-abstract-set"] // Methods "method" // = ["public-static-method", "protected-static-method", "private-static-method", "public-instance-method", "protected-instance-method", "private-instance-method", // "public-abstract-method", "protected-abstract-method"] ] ``` ### Member Group Types (Readonly Fields) It is possible to group fields by their `readonly` modifiers. ```jsonc [ // Index signature "readonly-signature", "signature", // Fields "readonly-field", // = ["public-static-readonly-field", "protected-static-readonly-field", "private-static-readonly-field", "public-instance-readonly-field", "protected-instance-readonly-field", "private-instance-readonly-field", "public-abstract-readonly-field", "protected-abstract-readonly-field"] "field" // = ["public-static-field", "protected-static-field", "private-static-field", "public-instance-field", "protected-instance-field", "private-instance-field", "public-abstract-field", "protected-abstract-field"] ] ``` ### Grouping Different Member Types at the Same Rank It is also possible to group different member types at the same rank. ```jsonc [ // Index signature "signature", // Fields "field", // Static initialization "static-initialization", // Constructors "constructor", // Getters and Setters at the same rank ["get", "set"], // Methods "method" ] ``` ## When Not To Use It If you don't care about the general order of your members, then you will not need this rule.