/** Returns the index of the first match, or -1 if no match */
findFirst(
1matchFct) {
	let elements = 
2this.elements;
	for (let i = 0; i < elements.length; i++) {
		let nextElem = elements.get(i);
		if (matchFct(nextElem))
			return i;
	}
	return -1;
}

class QueryArray {
	static from(elements) {
		return new this(elements);
	}
	constructor(elements) {
		this.elements = elements;
	}
	map(mapFct) {
		let newElements = Array.newDynamic();
		for (let nextElem of this.elements) {
			let newElem = mapFct(nextElem);
			newElements.add(newElem);
		}
		return QueryArray.from(newElements);
	}
	forEach(actionFct) {
		for (let nextElem of this.elements)
			actionFct(nextElem);
	}
	findFirst(matchFct) {
		let elements = this.elements;
		for (let i = 0; i < elements.length; i++) {
			let nextElem = elements.get(i);
			if (matchFct(nextElem))
				return i;
		}
		return -1;
	}
	toString() {
		return this.elements.toString();
	}
	printAll(label) {
		println(label);
		this.forEach(nextElem => println(nextElem.toString()));
	}
} _br_ _br_//Try It - map into array of countries

let array = Mathematician.
1newSampleSet1();
let qarray = QueryArray.
2from(array);
qarray.printAll();
let matchIndex =
	qarray.
3findFirst(next => next.getCountry().equals('Kenya'));


4println("\nIndex of first match: " + matchIndex);