See fast enumeration documentation. Basically you’d have, usually, an array, and you can obtain each item in the array with a handy loop instead of using NSEnumerator or an integer count variable. It makes your code much cleaner to ask for each NSString in your array rather than to have to assign to a variable … Read more
If keypairs is an array, then you should really iterate over the elements like: for(var i = 0; i < keypairs.length; i++) { … } If keypairs is a hash, then JSLint is correctly recommending that you check that you are operating on the appropriate key type (i.e., confirming that the hash is the expected … Read more
Yep – works in all loops. const myObject = { propA: ‘foo’, propB: ‘bar’ }; for (let propName in myObject) { console.log(propName); if (propName !== ‘propA’) { continue; } else if (propName === ‘propA’) { break; } } (By loops I mean for, for…in, for…of, while and do…while, not forEach, which is actually a function … Read more
Don’t iterate over arrays using for…in. That syntax is for iterating over the properties of an object, which isn’t what you’re after. As for your actual question, you can use the continue: var y = [1, 2, 3, 4]; for (var i = 0; i < y.length; i++) { if (y[i] == 2) { continue; … Read more
In Swift 2, new where syntax was added: for value in boolArray where value == true { … } In Pre 2.0 one solution would be to call .filter on the array before you iterate it: for value in boolArray.filter({ $0 == true }) { doSomething() }
There is no performance benefit offered by forEach. In fact, if you look at the source code, the forEach function actually simply performing for–in. For release builds, the performance overhead of this function over simply using for–in yourself is immaterial, though for debug builds, it results in an observable performance impact. The main advantage of … Read more
If set of operations to be applied to all elements of the array, it is possible to replace for-loop with forEach{} closure and use optional chaining: var arr: [Int]? = [1, 2, 3] arr?.forEach{print($0)}
It says, Use Object.{keys,values,entries}, and iterate over the resulting array. So you could do something like this to get the object keys as an array and then loop through the keys to make necessary changes. currentValues= {hey:1212, git:1212, nmo:12121} Object.keys(currentValues).forEach(function(key) { yield put(setCurrentValue(key, currentValues[key])); })
The current answers are good, but do not talk about how they are just syntactic sugar to some pattern that we are so used to. Let’s start with an example, say we have 10 numbers, and we want a subset of those that are greater than, say, 5. >>> numbers = [12, 34, 1, 4, … Read more
Use var, it reduces the scope of the variable otherwise the variable looks up to the nearest closure searching for a var statement. If it cannot find a var then it is global (if you are in a strict mode, using strict, global variables throw an error). This can lead to problems like the following. … Read more