feat(useMath): new function (#1935)

packages/math/useMath/index.md

@@ -0,0 +1,23 @@
+---
+category: '@Math'
+---
+
+# useMath
+
+Reactive `Math` methods.
+
+## Usage
+
+```ts
+import { useMath } from '@vueuse/math'
+
+const base = ref(2)
+const exponent = ref(3)
+const result = useMath('pow', base, exponent) // Ref<8>
+
+const num = ref(2)
+const root = useMath('sqrt', num) // Ref<1.4142135623730951>
+
+num.value = 4
+console.log(root.value) // 2
+```

packages/math/useMath/index.test.ts

@@ -0,0 +1,29 @@
+import { ref } from 'vue-demi'
+import { useMath } from '.'
+
+describe('useMath', () => {
+  it('should be defined', () => {
+    expect(useMath).toBeDefined()
+  })
+
+  it('should accept numbers', () => {
+    const v = useMath('pow', 2, 3)
+    expect(v.value).toBe(8)
+  })
+
+  it('should accept refs', () => {
+    const base = ref(2)
+    const exponent = ref(3)
+    const result = useMath('pow', base, exponent)
+
+    expect(result.value).toBe(8)
+
+    const num = ref(4)
+    const root = useMath('sqrt', num)
+
+    expect(root.value).toBe(2)
+
+    num.value = 16
+    expect(root.value).toBe(4)
+  })
+})

packages/math/useMath/index.ts

@@ -0,0 +1,16 @@
+import type { ArgumentsType, Reactified } from '@vueuse/shared'
+import { reactify } from '@vueuse/shared'
+
+export type UseMathKeys = keyof { [K in keyof Math as Math[K] extends (...args: any) => any ? K : never]: unknown }
+
+/**
+ * Reactive `Math` methods.
+ *
+ * @see https://vueuse.org/useMath
+ */
+export function useMath<K extends keyof Math>(
+  key: K,
+  ...args: ArgumentsType<Reactified<Math[K], true>>
+): ReturnType<Reactified<Math[K], true>> {
+  return reactify(Math[key] as any)(...args) as any
+}

packages/shared/utils/types.ts

@@ -62,6 +62,8 @@ export type ShallowUnwrapRef<T> = T extends Ref<infer P> ? P : T
 
 export type Awaitable<T> = Promise<T> | T
 
+export type ArgumentsType<T> = T extends (...args: infer U) => any ? U : never
+
 export interface Pausable {
   /**
    * A ref indicate whether a pusable instance is active