is-index-x
Determine whether the passed value is a zero based index.
module.exports(value, [length])
⇒ boolean
⏏
This method determines whether the passed value is a zero based index. JavaScript arrays are zero-indexed: the first element of an array is at index 0, and the last element is at the index equal to the value of the array's length property minus 1.
Kind: Exported function
Returns: boolean
- A Boolean indicating whether or not the given value is a zero based index within bounds.
Param | Type | Default | Description |
---|---|---|---|
value | number | string |
The value to be tested for being a zero based index. | |
[length] | number |
MAX_SAFE_INTEGER |
The length that sets the upper bound. |
Example
import isIndex from 'is-index-x';
console.log(isIndex(0)); // true
console.log(isIndex(1)); // true
console.log(isIndex('10')); // true
console.log(isIndex(-100000)); // false
console.log(isIndex(2 ** 53)); // false
console.log(isIndex(0.1)); // false
console.log(isIndex(Math.PI)); // false
console.log(isIndex(NaN)); // false
console.log(isIndex(Infinity)); // false
console.log(isIndex(-Infinity)); // false
console.log(isIndex(true)); // false
console.log(isIndex(false)); // false
console.log(isIndex([1])); // false
console.log(isIndex(10, 10)); // false