Code Muri

출처: The Art of Readable Code (번역서: 읽기 좋은 코드가 좋은 코드다)

☞ 개발자 강추 서적입니다.

변수와 관련된 3가지 문제점들이 있으며,

1. The more variables there are, the harder it is to keep track of them all.

2. The bigger a variable’s scope, the longer you have to keep track of it.

3. The more often a variable changes, the harder it is to keep track of its current value.

이러한 이슈를 처리하는 방법은 다음과 같습니다.

Eliminate Variables

• Useless Temporary Variables
• Eliminating Intermediate Results
• Eliminating Control Flow Variables

Shrink(Reduce) the Scope of Variables

• Creating "Private" Variables
• Moving Definitions Down

• const or final
• immutable or permanent

<input type="text" id="input1" value="Dustin">
<input type="text" id="input2" value="Trevor">
<input type="text" id="input3" value="">
<input type="text" id="input4" value="Melissa">
...

var setFirstEmptyInput = function (new_value) {
	var found = false;
	var i = 1;
	var elem = document.getElementById('input' + i);
	while (elem !== null) {
		if (elem.value === '') {
			found = true;
			break;
		}
		i++;
		elem = document.getElementById('input' + i);
	}
	if (found) elem.value = new_value;
	return elem;
};

var setFirstEmptyInput = function (new_value) {
	var i = 1;
	var elem = document.getElementById('input' + i);
	while (elem !== null) {
		if (elem.value === '') {
			elem.value = new_value;
			return elem;
		}
		i++;
		elem = document.getElementById('input' + i);
	}
	return null;
};

var setFirstEmptyInput = function (new_value) {
	for (var i = 1; true; i++) {
		var elem = document.getElementById('input' + i);
		if (elem === null)
			return null; // Search Failed. No empty input found.
		if (elem.value === '') {
			elem.value = new_value;
			return elem;
		}
	}
};