![]() When array_map() has completed running, the result will be a new array that contains our modified values. the second argument is the array we iterate over, and the body of the function are the commands we would put inside our foreach block. it may help, at the beginning, to think of this as just another way of writing a foreach loop. If this is the first time you've seen array_map() or if you've never experimented with any functional programming ideas before, this may seem confusing. the callable itself takes one argument, which is the current element of our input array. this function is what modifies the elements of our input array. this argument is an anonymous function, a ' callable' in fact. The first argument is the interesting part. the second argument is our $testArray the array we want to use as input. If we look at array_map(), we can see that it takes two arguments. this is all done in one line, the call to array_map(). we then create and return a new array called $result that contains all those values. ![]() The purpose of this code is take the array of integers in $testArray and double each of those numbers. let's look at an example:Įnter fullscreen mode Exit fullscreen mode the result of each of those function calls is then returned as an element of a new array. The basic purpose of array_map() is to take an array and apply a function to each of the elements in that array. a short digression about first class functions.addtionally, we'll go over several ways that we can define the callback functions these array functions require and look a bit at first class functions. We'll be looking at some basic examples, but also more complex ones that are a little closer to the sort of useful things we might want our code to do. In this article we're going to do a quick survey of three of php's powerful array manipulation functions: if you are new to the ideas like mapping, filtering and reducing, it may take some time to get used to thinking about array handling in this way, but the end result will be code that more concise and stable. Php's array_map(), array_filter() and array_reduce() functions allow us to handle arrays in a clean, concise and powerful way by letting us use ideas from functional programming. but there's a better way to manage our arrays. it's easy to let arrays get away on you and wind up writing complex, hard-to-test foreach loops to modify or filter your data. More clearly, om(obj, mapFn, thisArg) has the same result as om(obj).map(mapFn, thisArg), except that it does not create an intermediate array, and mapFn only receives two arguments ( element, index) without the whole array, because the array is still under construction.Php's arrays are great. If the arrayLike object is missing some index properties, they become undefined in the new array.Īom() has an optional parameter mapFn, which allows you to execute a function on each element of the array being created, similar to map(). To convert an async iterable to an array, use omAsync().Īom() never creates a sparse array. To convert an ordinary object that's not iterable or array-like to an array (by enumerating its property keys, values, or both), use Object.keys(), Object.values(), or Object.entries(). array-like objects (objects with a length property and indexed elements). ![]()
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