requirePrev()function
requirePrev(items: PossibleArray<T>, item: T, caller: AnyCaller = requirePrev): T
| Param | Type | |
|---|---|---|
items | PossibleArray<T> | The array or iterable to search. required |
item | T | The item to find the predecessor of. required |
caller | AnyCaller | Function to attribute a thrown error to (defaults to requirePrev itself). Defaults to requirePrev |
| Return | |
|---|---|
T | The item preceding item. |
| Throws | |
|---|---|
RequiredError | If item is missing or has no predecessor. |
Get the previous item from an array or iterable.
Examples
requirePrev([1, 2, 3], 2) // 1