vue-demi

What is vue-demi?

The vue-demi package is a utility that enables library authors to publish their libraries for both Vue 2 and Vue 3 with a single codebase. It provides a set of APIs that are compatible with both versions of Vue, allowing for seamless integration and use in projects that may be using either version.

What are vue-demi's main functionalities?

Unified Vue Hooks

vue-demi provides a way to detect the version of Vue being used and allows you to conditionally execute code based on the version. This is useful for handling differences in the Vue lifecycle hooks or other version-specific features.

import { isVue2, isVue3, Vue2, Vue3 } from 'vue-demi'

if (isVue2) {
  // Vue 2 specific logic
} else if (isVue3) {
  // Vue 3 specific logic
}

Reactive API

vue-demi exports the reactive composition API that is consistent across Vue 2 and Vue 3. This allows developers to use the reactive system without worrying about the underlying Vue version.

import { ref, reactive } from 'vue-demi'

const count = ref(0)
const state = reactive({ name: 'Vue' })

Effect API

vue-demi provides the effect function which is part of the reactivity system in Vue 3 and is made available for Vue 2 through this package. It allows you to run side effects when reactive data changes.

import { effect } from 'vue-demi'

effect(() => {
  console.log('This will run when reactive state changes')
})

Other packages similar to vue-demi

@vue/composition-api

This package is a plugin for Vue 2 that provides the Vue 3 Composition API. It is similar to vue-demi in that it allows developers to use Vue 3 features in Vue 2 applications, but it does not provide the same automatic compatibility layer for libraries to support both Vue 2 and Vue 3.

vue2-helpers

vue2-helpers is a set of helper functions for Vue 2 that aim to bring some of the Vue 3 functionality to Vue 2. While it provides similar bridging functionality, it is not as comprehensive as vue-demi and is more focused on specific helpers rather than a full compatibility layer.

README

vue-demi

WIP

Vue Demi (french "half") is a plugin dev utility that allows you to write Vue plugins for Vue 2 and 3 without worry about users' installed version. See more details in this blog.

Usage

Install this as your plugin's dependency:

{
  "dependencies": {
    "vue-demi": "*"
  }
}

import every thing from it, it will redirect to vue@2 @vue/composition-api or vue@next based on users' environments.

import { ref, reactive, defineComponent } from 'vue-demi'

Publish your plugin and all is done!