When to use ambient while searching for a type definition?

问题

I'm currently migrating from tsd to typings since it's deprecated. but It's not crystal clear when I need to use --ambient or not when looking for a definition.

Also: is it correct to say that the goal of typings, in the longterm, is to completely move away from ambiant declatation from DefintelyTyped and only rely on the typings registry?

回答1:

but It's not crystal clear when I need to use --ambient

Always Ambient Stuff

Stuff that changes the nature of the global environment (e.g. node.d.ts) will always be ambient.

Modules

For stuff that is a module (e.g. a node package like debug) it can be converted into a typings module (and in fact has been) so you don't need --ambient.

However you can still use the definition from DefinitelyTyped if you use --ambient. Also if the conversion hasn't taken place to typings you can only use --ambient.

来源：https://stackoverflow.com/questions/36397954/when-to-use-ambient-while-searching-for-a-type-definition