Object.has.call

// typescript definition
interface Object {
	has: (prop: string) => boolean;
}
// typescript
Object.prototype.has = function(this: { [key:string]: any }, prop) {
	return Object.prototype.hasOwnProperty(this, prop);
}
// javascript
Object.prototype.has = function(prop) {
	return Object.prototype.hasOwnProperty(this, prop);
}
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