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TypeScript 4.9 Iteration Plan · Issue #50457 · microsoft/TypeScript · GitHub
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PlanningIteration plans and roadmappingIteration plans and roadmapping
Description
This document outlines our focused tasks for TypeScript 4.9. It minimally indicates intent to investigate tasks or contribute to an implementation. Nothing is set in stone, but we will strive to complete these tasks in a reasonable timeframe.
| Date | Event |
|---|---|
| August 23rd | TypeScript 4.8 Release |
| September 16th | Create 4.9 Beta (4.9.1) Build for Testing |
| September 20th | TypeScript 4.9 Beta Release |
| October 28th | Create 4.9 RC (4.9.2) Build for Testing |
| November 1st | TypeScript 4.9 RC Release |
| November 11th | Create 4.9 Final (4.9.3) Build for Testing |
| November 15th | TypeScript 4.9 Final Release 🚀 |
gantt
dateFormat YYYY-MM-DD
TypeScript 4.8 Stabilization Period : 2022-08-05, 2022-08-25
TypeScript 4.9 Beta Development : 2022-08-05, 2022-09-16
TypeScript 4.9 RC Development : 2022-09-16, 2022-10-28
TypeScript 4.9 Stabilization Period : 2022-10-28, 2022-11-15
todayMarker stroke-width:5px,stroke:#0f0,opacity:0.5
Language and Compiler Features
- ECMAScript Decorators
- Contextually Typed And Compatible Operator
lib.d.tsUpdates- Support
.tsas a Module Specifier for Bundler/Loader Scenarios - Investigate Fine-Granularity Module Resolution Options
- Investigate Per-File Settings
- Make @types/web Versionable
- Investigate
--isolatedDeclarationEmit Mode
Editor Productivity
- Switch to FsEvents for File-Watching by Default
- Virtual File System Support in TSServer
- Investigate Cancellation in Browser Contexts
- Prototype Automatic Type Acquisition in Web Contexts
- Investigate TS Server Plugins on the Web
- High Confidence JavaScript Diagnostics in Classes
- Provide Walkthroughs in Visual Studio Code Welcome View
- Easy Run/Debug for Loose TypeScript Files
Performance
- Investigate Module Resolution Caching in
.tsbuildinfoFiles - Investigate Tooling for JIT Deoptimizations
- Investigate Outstanding Performance Issues
- Enrich TS Server Tracepoints
Infrastructure
- Enable
strictFunctionTypeson TypeScript Codebase - Determining Module Migration and Shipping Strategy
- Rewrite TSServer Crawler
- TSServer Performance Testing Infrastructure
Website
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