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useShorthandArrayType (since v1.0.0)

Diagnostic Category: lint/style/useShorthandArrayType

When expressing array types, this rule promotes the usage of T[] shorthand instead of Array<T>.

Examples

Section titled Examples

Invalid

Section titled Invalid
let invalid: Array<foo>;
style/useShorthandArrayType.js:1:14 lint/style/useShorthandArrayType  FIXABLE  ━━━━━━━━━━━━━━━━━━━━━

  ⚠ Use shorthand T[] syntax instead of Array<T> syntax.
  
  > 1 │ let invalid: Array<foo>;
      │              ^^^^^^^^^^
    2 │ 
  
  ℹ Unsafe fix: Use shorthand T[] syntax to replace
  
    1   │ - let·invalid:·Array<foo>;
      1 │ + let·invalid:·foo[];
    2 2 │   
  

let invalid: Promise<Array<string>>;
style/useShorthandArrayType.js:1:22 lint/style/useShorthandArrayType  FIXABLE  ━━━━━━━━━━━━━━━━━━━━━

  ⚠ Use shorthand T[] syntax instead of Array<T> syntax.
  
  > 1 │ let invalid: Promise<Array<string>>;
      │                      ^^^^^^^^^^^^^
    2 │ 
  
  ℹ Unsafe fix: Use shorthand T[] syntax to replace
  
    1   │ - let·invalid:·Promise<Array<string>>;
      1 │ + let·invalid:·Promise<string[]>;
    2 2 │   
  

let invalid: Array<Foo<Bar>>;
style/useShorthandArrayType.js:1:14 lint/style/useShorthandArrayType  FIXABLE  ━━━━━━━━━━━━━━━━━━━━━

  ⚠ Use shorthand T[] syntax instead of Array<T> syntax.
  
  > 1 │ let invalid: Array<Foo<Bar>>;
      │              ^^^^^^^^^^^^^^^
    2 │ 
  
  ℹ Unsafe fix: Use shorthand T[] syntax to replace
  
    1   │ - let·invalid:·Array<Foo<Bar>>;
      1 │ + let·invalid:·Foo<Bar>[];
    2 2 │   
  

let invalid: Array<[number, number]>;
style/useShorthandArrayType.js:1:14 lint/style/useShorthandArrayType  FIXABLE  ━━━━━━━━━━━━━━━━━━━━━

  ⚠ Use shorthand T[] syntax instead of Array<T> syntax.
  
  > 1 │ let invalid: Array<[number, number]>;
      │              ^^^^^^^^^^^^^^^^^^^^^^^
    2 │ 
  
  ℹ Unsafe fix: Use shorthand T[] syntax to replace
  
    1   │ - let·invalid:·Array<[number,·number]>;
      1 │ + let·invalid:·[number,·number][];
    2 2 │   
  

let invalid: Array<[number, number]>;
style/useShorthandArrayType.js:1:14 lint/style/useShorthandArrayType  FIXABLE  ━━━━━━━━━━━━━━━━━━━━━

  ⚠ Use shorthand T[] syntax instead of Array<T> syntax.
  
  > 1 │ let invalid: Array<[number, number]>;
      │              ^^^^^^^^^^^^^^^^^^^^^^^
    2 │ 
  
  ℹ Unsafe fix: Use shorthand T[] syntax to replace
  
    1   │ - let·invalid:·Array<[number,·number]>;
      1 │ + let·invalid:·[number,·number][];
    2 2 │   
  

let invalid: ReadonlyArray<string>;
style/useShorthandArrayType.js:1:14 lint/style/useShorthandArrayType  FIXABLE  ━━━━━━━━━━━━━━━━━━━━━

  ⚠ Use shorthand readonly T[] syntax instead of ReadonlyArray<T> syntax.
  
  > 1 │ let invalid: ReadonlyArray<string>;
      │              ^^^^^^^^^^^^^^^^^^^^^
    2 │ 
  
  ℹ Unsafe fix: Use shorthand readonly T[] syntax to replace
  
    1   │ - let·invalid:·ReadonlyArray<string>;
      1 │ + let·invalid:·readonly·string[];
    2 2 │

Valid

Section titled Valid
let valid: Array<Foo | Bar>;
let valid: Array<keyof Bar>;
let valid: Array<foo | bar>;
Section titled Related links