Experimental decorators warning in TypeScript compilation

typescript decorator visual-studio-code
bensiu picture bensiu · Jul 8, 2016 · Viewed 225.3k times · Source

I receive the warning...

Experimental support for decorators is a feature that is subject to change in a future release. Set the 'experimentalDecorators' option `to remove this warning.

... even though my compilerOptions in tsconfig.json have the following settings:

"emitDecoratorMetadata": true,
"experimentalDecorators": true,

What is weird is that some random classes that use decorators do not show that warning but the rest in the same project do.

What could cause such behavior in the TypeScript compiler?

Answer

linguamachina picture linguamachina · Jul 10, 2016

Although VS Code is a great editor for TypeScript projects, it needs a kick every now and again. Often, without warning, certain files cause it to freak out and complain. Mostly the fix seems to be to save and close all open files, then open tsconfig.json. After that you should be able to re-open the offending file without error. If it doesn't work, lather, rinse, and repeat.

If your tsconfig.json specifies its source files using the files array, IntelliSense will only function correctly if the file in question is referenced such that VS Code can find it by traversing the input file tree.

Edit: The 'reload window' command (added ages ago now) should solve this problem once and for all.

Related questions

How to implement a typescript decorator?

TypeScript 1.5 now has decorators. Could someone provide a simple example demonstrating the proper way to implement a decorator and describe what the arguments in the possible valid decorator signatures mean? declare type ClassDecorator = <TFunction extends Function>(target: TFunction) =&…

Read More
Angular2 Component @Input two way binding

I have a data driven Angular application. I have a toggle component which I pass in a toggled state. My issue is that the two way data binding does not seem to work unless i pass in the toggle boolean …

Read More
TypeScript: remove key from type/subtraction type

I want to define a generic type ExcludeCart<T> that is essentially T but with a given key (in my case, cart) removed. So, for instance, ExcludeCart<{foo: number, bar: string, cart: number}> would be {foo: …

Read More