Variable sum`Const`

sum: <T>(items: T[], keyFn?: (item: T) => number) => number

Sum a list, optionally by a numeric key function.

Type Declaration

- <T>(items: T[], keyFn?: (item: T) => number): number
- Type Parameters
  - T
  Parameters
  - items: T[]
  - OptionalkeyFn: (item: T) => number
  Returns number