Function filterMap

filterMap<Input, Output>(input, transform): Output[]
This is like calling input.map(transform).filter(item => item !=== undefined). But if I used that line typescript would get the output type wrong. Array.prototype.flatMap() is a standard and traditional alternative.
Type Parameters
- Input
- Output
Parameters
- input: Input[]
  The values to be handed to transform() one at a time.
- transform: ((input: Input, index: number) => undefined | Output)
  The function to be called on each input. index is the index of the current input, just like in Array.prototype.forEach().
  - - (input, index): undefined | Output
    - Parameters
      input: Input
      index: number
      Returns undefined | Output
Returns Output[]
The items returned by transform(), with any undefined items removed.
- Defined in misc.ts:335