Function count

count<T>(array, callbackfn): number
Counts how many items match the criteria in the callback function.
Type Parameters
- T
Parameters
- array: T[]
  The array.
- callbackfn: ((value: T, index: number, array: T[]) => boolean)
  The filtering function.
  - - (value, index, array): boolean
    - Parameters
      value: T
      index: number
      array: T[]
      Returns boolean
Returns number
The number of items that match the filter.