Add isNullish and isNonNullish functions to typed module

docs/typed/is-non-nullish.mdx

@@ -0,0 +1,23 @@
+---
+title: isNonNullish
+description: 'Checks if the given value is not null or undefined.'
+group: Typed
+---
+
+## Basic usage
+
+Pass in a value and get a boolean telling you if the value is not a Nullish.
+
+```ts
+import { isNonNullish } from 'radash'
+
+isNonNullish(null) // false
+isNonNullish(undefined) // false
+isNonNullish('') // true
+isNonNullish(0) // true
+isNonNullish(false) // true
+isNonNullish(NaN) // true
+isNonNullish([]) // true
+isNonNullish({}) // true
+
+```

docs/typed/is-nullish.mdx

@@ -0,0 +1,22 @@
+---
+title: isNullish
+description: 'Checks if the given value is null or undefined.'
+group: Typed
+---
+
+## Basic usage
+
+Pass in a value and get a boolean telling you if the value is a Nullish.
+
+```ts
+import { isNullish } from 'radash'
+
+isNullish(null) // true
+isNullish(undefined) // true
+isNullish(0) // false
+isNullish('') // false
+isNullish(false) // false
+isNullish(NaN) // false
+isNullish([]) // false
+isNullish({}) // false
+```

src/tests/typed.test.ts

@@ -20,7 +20,7 @@ describe('typed module', () => {
       assert.isFalse(result)
     })
     test('returns false for class instance', () => {
-      class Data {}
+      class Data { }
       const result = _.isArray(new Data())
       assert.isFalse(result)
     })
@@ -56,7 +56,7 @@ describe('typed module', () => {
       assert.isFalse(result)
     })
     test('returns false for class instance', () => {
-      class Data {}
+      class Data { }
       const result = _.isObject(new Data())
       assert.isFalse(result)
     })
@@ -117,7 +117,7 @@ describe('typed module', () => {
       assert.isFalse(result)
     })
     test('returns false for class instance', () => {
-      class Data {}
+      class Data { }
       const result = _.isFunction(new Data())
       assert.isFalse(result)
     })
@@ -172,7 +172,7 @@ describe('typed module', () => {
       assert.isFalse(result)
     })
     test('returns false for class instance', () => {
-      class Data {}
+      class Data { }
       const result = _.isString(new Data())
       assert.isFalse(result)
     })
@@ -212,7 +212,7 @@ describe('typed module', () => {
       assert.isFalse(result)
     })
     test('returns false for class instance', () => {
-      class Data {}
+      class Data { }
       const result = _.isNumber(new Data())
       assert.isFalse(result)
     })
@@ -247,7 +247,7 @@ describe('typed module', () => {
   })
 
   describe('isInt function', () => {
-    class Data {}
+    class Data { }
     test('returns false for non-number values', () => {
       assert.isFalse(_.isInt(undefined))
       assert.isFalse(_.isInt(null))
@@ -270,7 +270,7 @@ describe('typed module', () => {
   })
 
   describe('isFloat function', () => {
-    class Data {}
+    class Data { }
     test('returns false for non-number values', () => {
       assert.isFalse(_.isFloat(undefined))
       assert.isFalse(_.isFloat(null))
@@ -293,7 +293,7 @@ describe('typed module', () => {
   })
 
   describe('isEmpty function', () => {
-    class Data {}
+    class Data { }
     class Person {
       name: string = 'ray'
     }
@@ -320,8 +320,8 @@ describe('typed module', () => {
       assert.isFalse(_.isEmpty('abc'))
       assert.isFalse(_.isEmpty(String('abc')))
       assert.isFalse(_.isEmpty([1, 2, 3]))
-      assert.isFalse(_.isEmpty(function work() {}))
-      assert.isFalse(_.isEmpty(() => {}))
+      assert.isFalse(_.isEmpty(function work() { }))
+      assert.isFalse(_.isEmpty(() => { }))
       assert.isFalse(_.isEmpty(Symbol('')))
       assert.isFalse(_.isEmpty(Symbol('hello')))
       const map = new Map()
@@ -342,8 +342,8 @@ describe('typed module', () => {
       assert.isFalse(_.isDate('abc'))
       assert.isFalse(_.isDate(String('abc')))
       assert.isFalse(_.isDate([1, 2, 3]))
-      assert.isFalse(_.isDate(function work() {}))
-      assert.isFalse(_.isDate(() => {}))
+      assert.isFalse(_.isDate(function work() { }))
+      assert.isFalse(_.isDate(() => { }))
       assert.isFalse(_.isDate(Symbol('')))
       assert.isFalse(_.isDate(Symbol('hello')))
     })
@@ -353,16 +353,16 @@ describe('typed module', () => {
     test('return true for Promise values', () => {
       assert.isTrue(_.isPromise(new Promise(res => res(0))))
       assert.isTrue(_.isPromise(new Promise(res => res(''))))
-      assert.isTrue(_.isPromise((async () => {})()))
+      assert.isTrue(_.isPromise((async () => { })()))
     })
     test('return false for non-Date values', () => {
       assert.isFalse(_.isPromise(22))
       assert.isFalse(_.isPromise({ name: 'x' }))
       assert.isFalse(_.isPromise('abc'))
       assert.isFalse(_.isPromise(String('abc')))
       assert.isFalse(_.isPromise([1, 2, 3]))
-      assert.isFalse(_.isPromise(function work() {}))
-      assert.isFalse(_.isPromise(() => {}))
+      assert.isFalse(_.isPromise(function work() { }))
+      assert.isFalse(_.isPromise(() => { }))
       assert.isFalse(_.isPromise(Symbol('')))
       assert.isFalse(_.isPromise(Symbol('hello')))
       assert.isFalse(_.isPromise({ then: 2 }))
@@ -381,7 +381,7 @@ describe('typed module', () => {
       assert.isFalse(result)
     })
     test('returns false for empty class instance', () => {
-      class Data {}
+      class Data { }
       const input = new Data()
       const result = _.isSymbol(input)
       assert.isFalse(result)
@@ -541,4 +541,38 @@ describe('typed module', () => {
       assert.isFalse(_.isEqual([complex], [{ ...complex, num: 222 }]))
     })
   })
+
+  describe('isNullish function', () => {
+    test('returns true for null and undefined', () => {
+      assert.isTrue(_.isNullish(null))
+      assert.isTrue(_.isNullish(undefined))
+    })
+    test('returns false for non-nullish values', () => {
+      assert.isFalse(_.isNullish(0))
+      assert.isFalse(_.isNullish(''))
+      assert.isFalse(_.isNullish(false))
+      assert.isFalse(_.isNullish([]))
+      assert.isFalse(_.isNullish({}))
+      assert.isFalse(_.isNullish(() => { }))
+      assert.isFalse(_.isNullish(Symbol('')))
+      assert.isFalse(_.isNullish(new Date()))
+    })
+  })
+
+  describe('isNonNullish function', () => {
+    test('returns false for null and undefined', () => {
+      assert.isFalse(_.isNonNullish(null))
+      assert.isFalse(_.isNonNullish(undefined))
+    })
+    test('returns true for non-nullish values', () => {
+      assert.isTrue(_.isNonNullish(0))
+      assert.isTrue(_.isNonNullish(''))
+      assert.isTrue(_.isNonNullish(false))
+      assert.isTrue(_.isNonNullish([]))
+      assert.isTrue(_.isNonNullish({}))
+      assert.isTrue(_.isNonNullish(() => { }))
+      assert.isTrue(_.isNonNullish(Symbol('')))
+      assert.isTrue(_.isNonNullish(new Date()))
+    })
+  })
 })

src/typed.ts

@@ -104,3 +104,19 @@ export const isEqual = <TType>(x: TType, y: TType): boolean => {
   }
   return true
 }
+
+
+/**
+ * Checks if the given value is null or undefined.
+ */
+export const isNullish = (value: any): value is null | undefined => {
+  return value === null || value === undefined
+}
+
+
+/**
+ * Checks if the given value is not null or undefined.
+ */
+export const isNonNullish = <TType>(value: TType): value is Exclude<TType, null | undefined> => {
+  return value !== null && value !== undefined
+}