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The repository for high quality TypeScript type definitions

Language issues

There are a few problems in TypeScript that limit the expressiveness of the type declarations. This page tracks the known issues that we submitted or found on the TypeScript codeplex bugtracker.

If you know of a typing related issue not linked here please leave and issue in this repos or make a PR on the source-branch.


Get/set accessors in interfaces

482 and 1085

Allow to extend global variables like Date or Object to support libs like sugar.js

Use Static interfaces for ambient declarations in lib.d.ts

507 and 2364

Support optional ambient "this" pointer typing in callback/function signatures

declaring callback scope members


Allow additional parameters after in declarations


Add support for type unions


declarations cannot describe function 'try' on module


decaring types for array-based tuples

2333 (pending)

Cleanup or select lib.d.ts global namespace

2387 (closed)

export = not usable without claiming a name in the global namespace


Allow operators to work on custom types (via valueOf)

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