Type Improvements
Since the release of Vue2.0, we have been receiving requests for better integration of TypeScript. Since then, we have added official TypeScript type declarations for most of the core libraries (vue
, vue-router
, vuex
). However, when using the out-of-the-box Vue API, current integration is lacking. For example: TypeScript cannot easily infer the this
type in the default object-based API used by Vue. To make our Vue code work better with TypeScript, we need to use the vue-class-component decorator, which allows us to write Vue components using class-based syntax.
For users who prefer class-based APIs, this may be good enough, but what's a little bit worse is that users have to use different APIs just for type determination. This also makes migrating existing Vue codebases to TypeScript more challenging.
Earlier this year, TypeScript introduced some new features that allow TypeScript to better understand object literal-based APIs, which also makes it more possible to improve Vue’s type declarations. Daniel Rosenwasser from the TypeScript team launched an ambitious PR (now held by core team member Herrington Darkholme) that, once merged, will provide:
When using the default Vue API Correct type inference for
this
. This works great in single file components too!Type inference based on the
props
of the component'sprops
configuration. More importantly, - These improvements will benefit pure JavaScript users too!
, if you are using VSCode with the awesome Vetur extension, you will experience significant improvements in auto-completion hints and even type hints when using pure JavaScript in Vue components! This is because vue-language-server, the internal package that analyzes Vue components, can leverage the TypeScript compiler to extract more information about your code. In addition, any editor that supports the language service protocol can use vue-language-server to provide similar functionality.
##Running VSCode + Vetur + New Type Declaration
new-types
branch) and open it using VSCode + Vetur to try it out.Operations that TypeScript users may need
- Previously, we recommended configuring "allowSyntheticDefaultImports": true
- in
tsconfig.json
In order to cope with the changes in syntax, the following libraries that depend on Vue core types will have major version updates and need to be upgraded with Vue2.5:to use ES-style import syntax (
import Vue from 'vue'). New types will be officially converted to ES-style import/export syntax, so that the above configuration is not needed and users are required to use ES-style imports in all cases.
vuex - ,
vue-router
Now, when adding custom modules, users need to use,
vuex-router-sync,
vue-class-component.
interface VueConstructor - instead of
namespace Vue
If you use(difference comparison)
as ComponentOptions - to annotate your component configuration, like
computed
We try our best to reduce upgrade costs and make these type improvements compatible with the class-based API used in,
watch,
renderTypes such as life cycle hooks require manual type annotation.
vue-class-component
2.4.x until you are ready to upgrade.
Blueprint: TypeScript type support in vue-cli
The above is the detailed content of TypeScript improvements in Vue 2.5. For more information, please follow other related articles on the PHP Chinese website!

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