Add documentation for named exports and name default method as detect

This commit is contained in:
= 2023-08-03 09:21:14 +09:00
parent 66943d06b3
commit 76303b8a3a
2 changed files with 82 additions and 63 deletions

View file

@ -72,11 +72,17 @@ Example:
- `'Function'`
- `'Object'`
This method is also exported as `detect`, you can import it like this:
```js
import {detect} from '@sindresorhus/is';
```
Note: It will throw an error if you try to feed it object-wrapped primitives, as that's a bad practice. For example `new String('foo')`.
### is.{method}
All the below methods accept a value and returns a boolean for whether the value is of the desired type.
All the below methods accept a value and return a boolean for whether the value is of the desired type.
#### Primitives
@ -566,6 +572,18 @@ This can be useful to confirm that a value is a valid count of something, ie. 0
Returns `true` if the value is a string with only whitespace characters.
## Named Exports
Named exports allow tooling to perform tree-shaking, potentially reducing bundle size by including only code from the methods that are used.
Every method listed above is available as a named export. Each method is prefixed by either `is` or `assert` depending on usage.
For example:
```js
import {assertNull, isUndefined} from '@sindresorhus/is';
```
## Type guards
When using `is` together with TypeScript, [type guards](http://www.typescriptlang.org/docs/handbook/advanced-types.html#type-guards-and-differentiating-types) are being used extensively to infer the correct type inside if-else statements.

View file

@ -149,73 +149,73 @@ const getObjectType = (value: unknown): ObjectTypeName | undefined => {
return undefined;
};
const isObjectOfType = <T>(type: ObjectTypeName) => (value: unknown): value is T => getObjectType(value) === type;
function detect(value: unknown): TypeName {
if (value === null) {
return 'null';
}
switch (typeof value) {
case 'undefined': {
return 'undefined';
}
case 'string': {
return 'string';
}
case 'number': {
return Number.isNaN(value) ? 'NaN' : 'number';
}
case 'boolean': {
return 'boolean';
}
case 'function': {
return 'Function';
}
case 'bigint': {
return 'bigint';
}
case 'symbol': {
return 'symbol';
}
default:
}
if (isObservable(value)) {
return 'Observable';
}
if (isArray(value)) {
return 'Array';
}
if (isBuffer(value)) {
return 'Buffer';
}
const tagType = getObjectType(value);
if (tagType) {
return tagType;
}
if (value instanceof String || value instanceof Boolean || value instanceof Number) {
throw new TypeError('Please don\'t use object wrappers for primitive types');
}
return 'Object';
}
function hasPromiseApi<T = unknown>(value: unknown): value is Promise<T> {
return isFunction((value as Promise<T>)?.then) && isFunction((value as Promise<T>)?.catch);
}
const is = Object.assign(
(value: unknown): TypeName => {
if (value === null) {
return 'null';
}
switch (typeof value) {
case 'undefined': {
return 'undefined';
}
case 'string': {
return 'string';
}
case 'number': {
return Number.isNaN(value) ? 'NaN' : 'number';
}
case 'boolean': {
return 'boolean';
}
case 'function': {
return 'Function';
}
case 'bigint': {
return 'bigint';
}
case 'symbol': {
return 'symbol';
}
default:
}
if (isObservable(value)) {
return 'Observable';
}
if (isArray(value)) {
return 'Array';
}
if (isBuffer(value)) {
return 'Buffer';
}
const tagType = getObjectType(value);
if (tagType) {
return tagType;
}
if (value instanceof String || value instanceof Boolean || value instanceof Number) {
throw new TypeError('Please don\'t use object wrappers for primitive types');
}
return 'Object';
},
detect,
{
all: isAll,
any: isAny,
@ -238,6 +238,7 @@ const is = Object.assign(
class_: isClass,
dataView: isDataView,
date: isDate,
detect,
directInstanceOf: isDirectInstanceOf,
domElement: isDomElement,
emptyArray: isEmptyArray,
@ -380,7 +381,7 @@ export function isBigUint64Array(value: unknown): value is BigUint64Array {
}
export function isBlob(value: unknown): value is Blob {
return isObjectOfType<Blob>('Blob')(value);
return getObjectType(value) === 'Blob';
}
export function isBoolean(value: unknown): value is boolean {