It would be cool to annotate a method or property with a deprecated attribute

Proposal

If a warning could be issued when using a deprecated method or property it is easier to upgrade to a newer library version (only when the definitions are up to date of course)

Syntax: Same as JSDoc, a simple comment

/**
 * @deprecated Use other method
 */
public foo() {
}

If supported in .d.ts files, this would really help with upgrading to a newer version.