Initialization in variable declarations against recommended approach JS-0119
Anti-pattern
Minor
a month ago
—
a year old
Variable 'dateSelects2' should be initialized on declaration
3 var dateName;
4 var dateCheckBox;
5 var dateSelects;
6 var dateSelects2; 7
8 $(':checkbox').filter(function(){
9 return /^use_/.test($(this).attr('id'));Variable 'dateSelects' should be initialized on declaration
2 var dateFields = new Array();
3 var dateName;
4 var dateCheckBox;
5 var dateSelects; 6 var dateSelects2;
7
8 $(':checkbox').filter(function(){Variable 'dateCheckBox' should be initialized on declaration
1function processDateFields(){
2 var dateFields = new Array();
3 var dateName;
4 var dateCheckBox; 5 var dateSelects;
6 var dateSelects2;
7 Variable 'dateName' should be initialized on declaration
1function processDateFields(){
2 var dateFields = new Array();
3 var dateName; 4 var dateCheckBox;
5 var dateSelects;
6 var dateSelects2;
Description
In JavaScript, variables can be assigned during declaration, or at any point afterwards using an assignment statement. For example, in the following code, foo is initialized during declaration, while bar is initialized later.
var foo = 1;
var bar;
if (foo) {
bar = 1;
} else {
bar = 2;
}
Bad Practice
function foo() {
var bar;
let baz;
}
Recommended
function foo() {
var bar = 1;
let baz = 2;
const qux = 3;
}