The TypeScript 5.0 beta announcement adds const type parameters to the language. You can now add the const modifier on a type parameter of a function, method, or class like this:
The type of names in the above example is readonly ["Alice", "Bob", "Eve"]. Marking the type parameter as const behaves as if you had written as const at every use instead. The above code is equivalent to the following TypeScript, which was the only option before TypeScript 5.0:
Make parsing generic async arrow functions more strict in .tsx files
Previously esbuild's TypeScript parser incorrectly accepted the following code as valid:
let fn = async <T> () => {};
The official TypeScript parser rejects this code because it thinks it's the identifier async followed by a JSX element starting with <T>. So with this release, esbuild will now reject this syntax in .tsx files too. You'll now have to add a comma after the type parameter to get generic arrow functions like this to parse in .tsx files:
let fn = async <T,> () => {};
Allow the in and out type parameter modifiers on class expressions
TypeScript 4.7 added the in and out modifiers on the type parameters of classes, interfaces, and type aliases. However, while TypeScript supported them on both class expressions and class statements, previously esbuild only supported them on class statements due to an oversight. This release now allows these modifiers on class expressions too:
declare let Foo: any;
Foo = class <in T> { };
Foo = class <out T> { };
The TypeScript 5.0 beta announcement adds const type parameters to the language. You can now add the const modifier on a type parameter of a function, method, or class like this:
The type of names in the above example is readonly ["Alice", "Bob", "Eve"]. Marking the type parameter as const behaves as if you had written as const at every use instead. The above code is equivalent to the following TypeScript, which was the only option before TypeScript 5.0:
Make parsing generic async arrow functions more strict in .tsx files
Previously esbuild's TypeScript parser incorrectly accepted the following code as valid:
let fn = async <T> () => {};
The official TypeScript parser rejects this code because it thinks it's the identifier async followed by a JSX element starting with <T>. So with this release, esbuild will now reject this syntax in .tsx files too. You'll now have to add a comma after the type parameter to get generic arrow functions like this to parse in .tsx files:
let fn = async <T,> () => {};
Allow the in and out type parameter modifiers on class expressions
TypeScript 4.7 added the in and out modifiers on the type parameters of classes, interfaces, and type aliases. However, while TypeScript supported them on both class expressions and class statements, previously esbuild only supported them on class statements due to an oversight. This release now allows these modifiers on class expressions too:
declare let Foo: any;
Foo = class <in T> { };
Foo = class <out T> { };
Dependabot will resolve any conflicts with this PR as long as you don't alter it yourself. You can also trigger a rebase manually by commenting @dependabot rebase.
Dependabot commands and options
You can trigger Dependabot actions by commenting on this PR:
- `@dependabot rebase` will rebase this PR
- `@dependabot recreate` will recreate this PR, overwriting any edits that have been made to it
- `@dependabot merge` will merge this PR after your CI passes on it
- `@dependabot squash and merge` will squash and merge this PR after your CI passes on it
- `@dependabot cancel merge` will cancel a previously requested merge and block automerging
- `@dependabot reopen` will reopen this PR if it is closed
- `@dependabot close` will close this PR and stop Dependabot recreating it. You can achieve the same result by closing it manually
- `@dependabot ignore this major version` will close this PR and stop Dependabot creating any more for this major version (unless you reopen the PR or upgrade to it yourself)
- `@dependabot ignore this minor version` will close this PR and stop Dependabot creating any more for this minor version (unless you reopen the PR or upgrade to it yourself)
- `@dependabot ignore this dependency` will close this PR and stop Dependabot creating any more for this dependency (unless you reopen the PR or upgrade to it yourself)
Bumps esbuild from 0.17.4 to 0.17.5.
Release notes
Sourced from esbuild's releases.
... (truncated)
Changelog
Sourced from esbuild's changelog.
... (truncated)
Commits
a8b660d
publish 0.17.5 to npm0c3642e
fix constant folding bug with nested operandsbe94d37
updateenum
constant folding for TypeScript 5.073523d9
parseconst
type parameters from TypeScript 5.03ada8f0
test coverage forasync \<A, B>
in typescript8824778
tsx: reject generic arrow functions without a,
1291b59
forbid definite assignment assertions on methods71b3ef9
allowin
andout
with class expression paramsDependabot will resolve any conflicts with this PR as long as you don't alter it yourself. You can also trigger a rebase manually by commenting
@dependabot rebase
.Dependabot commands and options
You can trigger Dependabot actions by commenting on this PR: - `@dependabot rebase` will rebase this PR - `@dependabot recreate` will recreate this PR, overwriting any edits that have been made to it - `@dependabot merge` will merge this PR after your CI passes on it - `@dependabot squash and merge` will squash and merge this PR after your CI passes on it - `@dependabot cancel merge` will cancel a previously requested merge and block automerging - `@dependabot reopen` will reopen this PR if it is closed - `@dependabot close` will close this PR and stop Dependabot recreating it. You can achieve the same result by closing it manually - `@dependabot ignore this major version` will close this PR and stop Dependabot creating any more for this major version (unless you reopen the PR or upgrade to it yourself) - `@dependabot ignore this minor version` will close this PR and stop Dependabot creating any more for this minor version (unless you reopen the PR or upgrade to it yourself) - `@dependabot ignore this dependency` will close this PR and stop Dependabot creating any more for this dependency (unless you reopen the PR or upgrade to it yourself)