Sometimes, we want to add global types in TypeScript.
In this article, we’ll look at how to add global types in TypeScript.
How to add global types in TypeScript?
To add global types in TypeScript, we can add the declare global
statement in a .d.ts
file.
For instance, we write
declare global {
interface String {
fancyFormat(opts: StringFormatOptions): string;
}
}
to add the String
interface into the global
type declaration to add the fancyFormat
method to a string object.
We specify the signature of it with (opts: StringFormatOptions)
and we specify that it returns a string
.
Conclusion
To add global types in TypeScript, we can add the declare global
statement in a .d.ts
file.