57bd60818c
Component commits: 628da10d8a Eliminate redundant or meaningless elaborations in type relations a009ee1116 Accept new baselines a65794c84d Add resetErrorInfo (though, oddly, shouldn't be necessary) f269f4252c Less aggressive reduction in second pass union/intersection checks 1312e8a420 Accept new baselines b82966fbaa Restructure and back off a little bit more f0b87421ed Only cache union/intersection relations once 9404e06128 Accept new baselines 4866ce562d Properly cache identity relations, clean up error reporting 2670b26187 Move more logic to cached side of relation checks adb37a5abb Optimize and remove more redundant elaborations 16b986bd5f Accept new baselines 1c69acb43d Remove unnecessary error state capture 530c8765d5 More optimizing 25a71c4de6 Cache isWeakType computation c427a46aff Revert "Cache isWeakType computation" This reverts commit 25a71c4de61f6366ffac080d19685dcb200f42b9. 1d70b01236 Address CR feedback 28439f7028 Merge branch 'main' into fix47668 # Conflicts: # src/compiler/diagnosticMessages.json c472ba5087 Accept new baselines Co-authored-by: Anders Hejlsberg <andersh@microsoft.com>
TypeScript
TypeScript is a language for application-scale JavaScript. TypeScript adds optional types to JavaScript that support tools for large-scale JavaScript applications for any browser, for any host, on any OS. TypeScript compiles to readable, standards-based JavaScript. Try it out at the playground, and stay up to date via our blog and Twitter account.
Find others who are using TypeScript at our community page.
Installing
For the latest stable version:
npm install -g typescript
For our nightly builds:
npm install -g typescript@next
Contribute
There are many ways to contribute to TypeScript.
- Submit bugs and help us verify fixes as they are checked in.
- Review the source code changes.
- Engage with other TypeScript users and developers on StackOverflow.
- Help each other in the TypeScript Community Discord.
- Join the #typescript discussion on Twitter.
- Contribute bug fixes.
- Read the archived language specification (docx, pdf, md).
This project has adopted the Microsoft Open Source Code of Conduct. For more information see the Code of Conduct FAQ or contact opencode@microsoft.com with any additional questions or comments.
Documentation
Building
In order to build the TypeScript compiler, ensure that you have Git and Node.js installed.
Clone a copy of the repo:
git clone https://github.com/microsoft/TypeScript.git
Change to the TypeScript directory:
cd TypeScript
Install Gulp tools and dev dependencies:
npm install -g gulp
npm ci
Use one of the following to build and test:
gulp local # Build the compiler into built/local.
gulp clean # Delete the built compiler.
gulp LKG # Replace the last known good with the built one.
# Bootstrapping step to be executed when the built compiler reaches a stable state.
gulp tests # Build the test infrastructure using the built compiler.
gulp runtests # Run tests using the built compiler and test infrastructure.
# You can override the specific suite runner used or specify a test for this command.
# Use --tests=<testPath> for a specific test and/or --runner=<runnerName> for a specific suite.
# Valid runners include conformance, compiler, fourslash, project, user, and docker
# The user and docker runners are extended test suite runners - the user runner
# works on disk in the tests/cases/user directory, while the docker runner works in containers.
# You'll need to have the docker executable in your system path for the docker runner to work.
gulp runtests-parallel # Like runtests, but split across multiple threads. Uses a number of threads equal to the system
# core count by default. Use --workers=<number> to adjust this.
gulp baseline-accept # This replaces the baseline test results with the results obtained from gulp runtests.
gulp lint # Runs eslint on the TypeScript source.
gulp help # List the above commands.
Usage
node built/local/tsc.js hello.ts
Roadmap
For details on our planned features and future direction please refer to our roadmap.