TypeScript
The official blog of the TypeScript team.
Latest posts
Announcing TypeScript 5.6 Beta
Today we are excited to announce the availability of TypeScript 5.6 Beta. To get started using the beta, you can get it through NuGet, or through npm with the following command: Here's a quick list of what's new in TypeScript 5.6! Disallowed Nullish and Truthy Checks Maybe you've written a regex and forgotten to call on it: or maybe you've accidentally written (which creates an arrow function) instead of (the greater-than-or-equal-to operator): or maybe you've tried to use a default value with , but mixed up the precedence of and a comparison operator like : or...
Announcing TypeScript 5.5
Today we're excited to announce the release of TypeScript 5.5! If you're not familiar with TypeScript, it's a language that builds on top of JavaScript by making it possible to declare and describe types. Writing types in our code allows us to explain intent and have other tools check our code to catch mistakes like typos, issues with and , and more. Types also power TypeScript's editor tooling like the auto-completion, code navigation, and refactorings that you might see in editors like Visual Studio and VS Code. In fact, if you write JavaScript in either of those editors, that experience is powered by Type...
Announcing TypeScript 5.5 RC
Today we are excited to announce the availability of the release candidate of TypeScript 5.5. To get started using the RC, you can get it through NuGet, or through npm with the following command: Here's a quick list of what's new in TypeScript 5.5! What's New Since the Beta? Since the beta, we've made a few changes that we wanted to call out. For one, we added support for ECMAScript's new methods. Additionally, we've adjusted the behavior of TypeScript's new regular expression checking to be slightly more lenient, while still erroring on questionable escapes tha...
Announcing TypeScript 5.5 Beta
Today we are excited to announce the availability of TypeScript 5.5 Beta. To get started using the beta, you can get it through NuGet, or through npm with the following command: Here's a quick list of what's new in TypeScript 5.5! Inferred Type Predicates This section was written by Dan Vanderkam, who implemented this feature in TypeScript 5.5. Thanks Dan! TypeScript's control flow analysis does a great job of tracking how the type of a variable changes as it moves through your code: By making you handle the case, TypeScript pushes you to write more robust code...
Announcing TypeScript 5.4
Today we're excited to announce the release of TypeScript 5.4! If you're not familiar with TypeScript, it's a language that builds on top of JavaScript by making it possible to declare and describe types. Writing types in our code allows us to explain intent and have other tools check our code to catch mistakes like typos, issues with and , and more. Types also power TypeScript's editor tooling like the auto-completion, code navigation, and refactorings that you might see in Visual Studio and VS Code. In fact, if you've been writing JavaScript in either of those editors, you've been using TypeScript all this...
Announcing TypeScript 5.4 RC
Today we're excited to announce our Release Candidate of TypeScript 5.4! Between now and the stable release of TypeScript 5.4, we expect no further changes apart from critical bug fixes. To get started using the RC, you can get it through NuGet, or through npm with the following command: Here's a quick list of what's new in TypeScript 5.4! What's New Since the Beta? Since the beta, we've updated the release notes to document new notable behavioral changes, including restrictions around enum compatibility, restrictions on enum member naming, and improvements in mapped type behavior. Pre...
Announcing TypeScript 5.4 Beta
Today we are excited to announce the availability of TypeScript 5.4 Beta. To get started using the beta, you can get it through NuGet, or through npm with the following command: Here's a quick list of what's new in TypeScript 5.4! Preserved Narrowing in Closures Following Last Assignments TypeScript can usually figure out a more specific type for a variable based on checks that you might perform. This process is called narrowing. One common pain-point was that these narrowed types weren't always preserved within function closures. Here, TypeScript decided that it wasn't "safe...
Announcing TypeScript 5.3
Today we're excited to announce the release of TypeScript 5.3! If you're not familiar with TypeScript, it's a language that adds type syntax to JavaScript to bring type-checking. Type-checking can catch all sorts of issues like typos and forgetting to check for and . But types go beyond type-checking - the same analyses of TypeScript's type-checker are used for rich editor tooling like auto-completion, code navigation, and refactorings. In fact, if you've been writing JavaScript in editors like Visual Studio or VS Code, that experience is powered by TypeScript! To get started using TypeScript, you can get i...
Announcing TypeScript 5.3 RC
Today we're excited to announce our Release Candidate of TypeScript 5.3! Between now and the stable release of TypeScript 5.3, we expect no further changes apart from critical bug fixes. To get started using the RC, you can get it through NuGet, or through npm with the following command: Here's a quick list of what's new in TypeScript 5.3! What's New Since the Beta? The beta permitted to be used across module resolution settings, but did not document it. Since the beta was released, we've added an option to prefer -only auto-imports when possible. Import Attributes TypeScr...