External module "utils/index-of/docs/types/index.d"

Export assignment indexOf

• indexOf(arr: Collection, searchElement: any, fromIndex?: undefined | number): number

• Returns the first index at which a given element can be found.

  Notes

  • Search is performed using strict equality comparison.

  throws

  fromIndex must be an integer

  Parameters

  • arr: Collection

    array-like object

  • searchElement: any

    element to find

  • Optional fromIndex: undefined | number

    starting index (if negative, the start index is determined relative to last element)

  Returns number

  index or -1

  Example

  var arr = [ 4, 3, 2, 1 ];
  var idx = indexOf( arr, 3 );
  // returns 1

  Example

  var arr = [ 4, 3, 2, 1 ];
  var idx = indexOf( arr, 5 );
  // returns -1

  Example

  // Using a `fromIndex`:
  var arr = [ 1, 2, 3, 4, 5, 2, 6 ];
  var idx = indexOf( arr, 2, 3 );
  // returns 5

  Example

  // `fromIndex` which exceeds `array` length:
  var arr = [ 1, 2, 3, 4, 2, 5 ];
  var idx = indexOf( arr, 2, 10 );
  // returns -1

  Example

  // Negative `fromIndex`:
  var arr = [ 1, 2, 3, 4, 5, 2, 6, 2 ];
  var idx = indexOf( arr, 2, -4 );
  // returns 5
  
  idx = indexOf( arr, 2, -1 );
  // returns 7

  Example

  // Negative `fromIndex` exceeding input `array` length:
  var arr = [ 1, 2, 3, 4, 5, 2, 6 ];
  var idx = indexOf( arr, 2, -10 );
  // returns 1

  Example

  // Array-like objects:
  var str = 'bebop';
  var idx = indexOf( str, 'o' );
  // returns 3