I want to have a variable in a TypeScript class that is of the type "boolean isVisible()".
ps - This seems so basic but 10 minutes of searching and I couldn't find it.
function boolfn() { return true; }
function strfn() { return 'hello world'; }
var x: () => boolean;
x = strfn; // Not OK
x = boolfn; // OK
var y = x(); // y: boolean
Here's one way of doing it, though I'll be happy to work with you to figure out exactly what you're trying to achieve.
export module Sayings {
export class Greeter {
isVisible(): boolean {
return true;
}
}
}
var greeter = new Sayings.Greeter();
var visible = greeter.isVisible();
You could also use a property instead of a function. Your original question talks about a "variable" and a "function" as if they're the same thing, but that's not necessarily the case.
export module Sayings {
export class Greeter {
isVisible: boolean = false;
}
}
var greeter = new Sayings.Greeter();
var visible = greeter.isVisible;
greeter.isVisible = true;
Or something like this maybe?
export module Sayings {
export class Greeter {
constructor(public isVisible: () => boolean) {
}
}
}
var someFunc = () => {
return false;
}
var greeter = new Sayings.Greeter(someFunc);
var visible = greeter.isVisible();
