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+# is [![Build Status](https://travis-ci.org/sindresorhus/is.svg?branch=master)](https://travis-ci.org/sindresorhus/is)
+
+> Type check values: `is.string('🦄') //=> true`
+
+<img src="header.gif" width="182" align="right">
+
+
+## Install
+
+```
+$ npm install @sindresorhus/is
+```
+
+
+## Usage
+
+```js
+const is = require('@sindresorhus/is');
+
+is('🦄');
+//=> 'string'
+
+is(new Map());
+//=> 'Map'
+
+is.number(6);
+//=> true
+```
+
+
+## API
+
+### is(value)
+
+Returns the type of `value`.
+
+Primitives are lowercase and object types are camelcase.
+
+Example:
+
+- `'undefined'`
+- `'null'`
+- `'string'`
+- `'symbol'`
+- `'Array'`
+- `'Function'`
+- `'Object'`
+
+Note: It will throw 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.
+
+#### Primitives
+
+##### .undefined(value)
+##### .null(value)
+##### .string(value)
+##### .number(value)
+##### .boolean(value)
+##### .symbol(value)
+
+#### Built-in types
+
+##### .array(value)
+##### .function(value)
+##### .buffer(value)
+##### .object(value)
+
+Keep in mind that [functions are objects too](https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Functions).
+
+##### .regExp(value)
+##### .date(value)
+##### .error(value)
+##### .nativePromise(value)
+##### .promise(value)
+
+Returns `true` for any object with a `.then()` and `.catch()` method. Prefer this one over `.nativePromise()` as you usually want to allow userland promise implementations too.
+
+##### .map(value)
+##### .set(value)
+##### .weakMap(value)
+##### .weakSet(value)
+
+#### Typed arrays
+
+##### .int8Array(value)
+##### .uint8Array(value)
+##### .uint8ClampedArray(value)
+##### .int16Array(value)
+##### .uint16Array(value)
+##### .int32Array(value)
+##### .uint32Array(value)
+##### .float32Array(value)
+##### .float64Array(value)
+
+#### Structured data
+
+##### .arrayBuffer(value)
+##### .sharedArrayBuffer(value)
+##### .dataView(value)
+
+#### Miscellaneous
+
+##### .nan(value)
+##### .nullOrUndefined(value)
+##### .primitive(value)
+
+JavaScript primitives are as follows: `null`, `undefined`, `string`, `number`, `boolean`, `symbol`.
+
+##### .integer(value)
+##### .plainObject(value)
+
+An object is plain if it's created by either `{}`, `new Object()`, or `Object.create(null)`.
+
+##### .iterable(value)
+##### .typedArray(value)
+
+
+## FAQ
+
+### Why yet another type checking module?
+
+There are hundreds of type checking modules on npm, unfortunately, I couldn't find any that fit my needs:
+
+- Includes both type methods and ability to get the type
+- Types of primitives returned as lowercase and object types as camelcase
+- Covers all built-ins
+- Unsurprising behavior
+- Well-maintained
+- Comprehensive test suite
+
+For the ones I found, pick 3 of these.
+
+The most common mistakes I noticed in these modules was using `instanceof` for type checking, forgetting that functions are objects, and omitting `symbol` as a primitive.
+
+
+## Related
+
+- [is-stream](https://github.com/sindresorhus/is-stream) - Check if something is a Node.js stream
+- [is-observable](https://github.com/sindresorhus/is-observable) - Check if a value is an Observable
+- [file-type](https://github.com/sindresorhus/file-type) - Detect the file type of a Buffer/Uint8Array
+- [is-ip](https://github.com/sindresorhus/is-ip) - Check if a string is an IP address
+- [is-array-sorted](https://github.com/sindresorhus/is-array-sorted) - Check if an Array is sorted
+- [is-error-constructor](https://github.com/sindresorhus/is-error-constructor) - Check if a value is an error constructor
+- [is-empty-iterable](https://github.com/sindresorhus/is-empty-iterable) - Check if an Iterable is empty
+
+
+## License
+
+MIT © [Sindre Sorhus](https://sindresorhus.com)