TypeScript 4.1 Beta Brings Template Literal Types

TSLint[46] scans TypeScript code for conformance to a set of standards and guidelines. ESLint, a standard JavaScript linter, also provided some support for TypeScript via community plugins. However, ESLint's inability to leverage TypeScript's language services precluded certain forms of semantic linting and program-wide analysis.[47] In early 2019, the TSLint team announced the linter's deprecation in favor of typescript-eslint, a joint effort of the TSLint, ESLint and TypeScript teams to consolidate linting under the ESLint umbrella for improved performance, community unity and developer accessibility.[48]

TypeScript 4.1 beta brings template literal types

The next improvement is support for symbol and template string pattern index signatures. TypeScript uses index signatures so developers can describe objects where every property has to have a certain type. This means developers can use such objects as dictionary-like types, with string keys to index into them with square brackets. 041b061a72