Prefer var declarations be placed at the top of their scope JS-0102
Anti-pattern
Minor
6 months ago
—
3 years old
All 'var' declarations must be at the top of the function scope
1417 },
1418 ],
1419 };
1420 var check = intersectionCheck(geoJson);1421 //join array elements with whitespace and comma
1422 req.body["yirmibesbin"] = check.yirmibes.join(", ");
1423 req.body["yuzbin"] = check.yuz.join(", ");All 'var' declarations must be at the top of the function scope
1400 req.body["datum"]
1401 );
1402 coordinates.push([parseFloat(close.lng), parseFloat(close.lat)]);
1403 var geoJson = {1404 type: "FeatureCollection",1405 features: [1406 {1407 type: "Feature",1408 properties: {1409 mytag: "datdat",1410 name: "datdat",1411 tessellate: true,1412 },1413 geometry: {1414 type: "Polygon",1415 coordinates: [coordinates],1416 },1417 },1418 ],1419 };1420 var check = intersectionCheck(geoJson);
1421 //join array elements with whitespace and comma
1422 req.body["yirmibesbin"] = check.yirmibes.join(", ");All 'var' declarations must be at the top of the function scope
1393 coordinates.push([cornerPoint.lng, cornerPoint.lat]);
1394 }
1395
1396 var close = converter(1397 parseFloat(corners[0].split(",")[0]),1398 parseFloat(corners[0].split(",")[1]),1399 req.body["zone"].length > 1 ? req.body["zone"][0] : req.body["zone"][0],1400 req.body["datum"]1401 );1402 coordinates.push([parseFloat(close.lng), parseFloat(close.lat)]);
1403 var geoJson = {
1404 type: "FeatureCollection",All 'var' declarations must be at the top of the function scope
1384 var x = parseFloat(cornerCoordinates[0]);
1385 var y = parseFloat(cornerCoordinates[1]);
1386
1387 var cornerPoint = converter(1388 x,1389 y,1390 req.body["zone"].length > 1 ? req.body["zone"][i] : req.body["zone"][0],1391 req.body["datum"]1392 );1393 coordinates.push([cornerPoint.lng, cornerPoint.lat]);
1394 }
1395All 'var' declarations must be at the top of the function scope
1382 var corner = corners[i];
1383 var cornerCoordinates = corner.split(",");
1384 var x = parseFloat(cornerCoordinates[0]);
1385 var y = parseFloat(cornerCoordinates[1]);1386
1387 var cornerPoint = converter(
1388 x,
Description
Declare variables at the top of their scope as it improves code readability, performance and also helps in code navigation.
The vars-on-top rule generates warnings when variable declarations are not used serially at the top of a function scope or the top of a program. By default variable declarations are always moved (“hoisted”) invisibly to the top of their containing scope by the JavaScript interpreter. This rule forces the programmer to represent that behavior by manually moving the variable declaration to the top of its containing scope.
Bad Practice
// Variable declarations in a block:
function doSomething() {
var first;
if (true) {
first = true;
}
var second;
}
// Variable declaration in for initializer:
function doSomething() {
for (var i=0; i<10; i++) {}
}
Recommended
function doSomething() {
var first;
var second; //multiple declarations are allowed at the top
if (true) {
first = true;
}
}
function doSomething() {
var i;
for (i=0; i<10; i++) {}
}