Fixes #20703 with solution suggested in https://github.com/Microsoft/TypeScript/issues/20703#issuecomment-361434795 Previously, `--isolatedModules` gave an error for any ambient const enum, which meant that some third-party libraries would always give errors even if the ambient const enums they declare were never used. Now, we only give an error when an ambient const enum is referenced, which allows such libraries to still be used as long as the const enums are never accessed. Some nuances: * As before, the error is only surfaced for *ambient* const enums. With non-ambient const enums, we know that an `isolatedModules` build will emit the enum and produce a plain reference rather than inlining the constant, so everything will still work. * I originally planned to do this check in the code path that inlines the constant, but that code is only exercised at emit time, so, for example, the TS language service wasn't giving an error in my editor. Instead, I do the check at typecheck time next to another const-enum-related check. * This can be a breaking change when using `skipLibCheck` because the error is typically moved from a .d.ts file to a .ts file. Testing done: I ran this TS build on a large project of mine that previously had disabled `isolatedModules` so I could use the `chalk` library. With `isolatedModules` enabled, there was no longer an error in the chalk typedefs, and a reference to the `Level` const enum produced an error in my editor. |
||
---|---|---|
.github | ||
.vscode | ||
bin | ||
doc | ||
lib | ||
scripts | ||
src | ||
tests | ||
.editorconfig | ||
.gitattributes | ||
.gitignore | ||
.gitmodules | ||
.mailmap | ||
.npmignore | ||
.npmrc | ||
.travis.yml | ||
AUTHORS.md | ||
CODE_OF_CONDUCT.md | ||
CONTRIBUTING.md | ||
CopyrightNotice.txt | ||
Gulpfile.js | ||
Jakefile.js | ||
LICENSE.txt | ||
package.json | ||
README.md | ||
ThirdPartyNoticeText.txt | ||
tslint.json |
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.
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.
- Join the #typescript discussion on Twitter.
- Contribute bug fixes.
- Read the 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 Jake tools and dev dependencies:
npm install -g jake
npm install
Use one of the following to build and test:
jake local # Build the compiler into built/local
jake clean # Delete the built compiler
jake LKG # Replace the last known good with the built one.
# Bootstrapping step to be executed when the built compiler reaches a stable state.
jake tests # Build the test infrastructure using the built compiler.
jake runtests # Run tests using the built compiler and test infrastructure.
# You can override the host or specify a test for this command.
# Use host=<hostName> or tests=<testPath>.
jake runtests-browser # Runs the tests using the built run.js file. Syntax is jake runtests. Optional
parameters 'host=', 'tests=[regex], reporter=[list|spec|json|<more>]'.
jake baseline-accept # This replaces the baseline test results with the results obtained from jake runtests.
jake lint # Runs tslint on the TypeScript source.
jake 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.