How to read the reference documentation
Please take a moment to familiarize yourself with the types of symbols you'll see throughout the technical documentation.
Type Annotations#
This shorthand is used to indicate the types of arguments, return values, and object properties.
| Annotation | Meaning |
|---|---|
[day] | The parameter is optional. If it is not supplied, it will be undefined. |
[day="Monday"] | The parameter is optional, but will be supplied a default value if not provided. |
?Array | Type can be an Array OR null. |
!Array | Type must be an Array; cannot be null. Primitive types (string, number, boolean) imply ! unless explicitly denoted otherwise with ?. |
| `string | number` |
{foo:number, bar:string} | Type is an object with two properties: foo, which is type number; and bar, which is type string. |
string[] | Type is an array of strings. |
Array<string> | Type is an array of strings. |
Promise<string> | Type is a Promise that is asynchronously fulfilled with a string. |
* | Can be any type. NOTE: In this early stage, * is sometimes used as a placeholder for incomplete documentation. |
