Why does my sample code result in the first string still having a trailing space? $a=array('test_data_1 ','test_data_2'); array_walk($a, 'trim'); array_map('trim', $a); foreach($a AS $b){ var_du...

array_map asks for the $array input as the last parameter(s). array_filter and array_reduce take $array input as the first parameter. As a contrasting example, when you call map, filter or reduce o...

The PowerShell range operator generates a list of values: >1..6 1 2 3 4 5 6 How can I generate a list of values with a specific step? For example, I need a list from 1 to 10 with step 2.

I really like the functional programming style of using array map to create an array of objects from another array of objects. $newObjects = array_map( function($oldObject) { return new NewObjec...

Suppose I have an associative array: $array = array( "key1" => "value", "key2" => "value2"); And I wanted to make the keys all uppercase. How would I do than in a generalized way ...

Clojure has an array-map and hash-map, I couldn't figure out the difference between the two. Could anyone explain if possible with an example as to when either of them would be used?

I found following solution here on StackOverflow to get an array of a specific object property from array of objects: PHP - Extracting a property from an array of objects The proposed solution is ...

Using: for($i=1; $i<= 10000; ++$i) { $arrayOfNumbers[] = rand(1, 99999); } Can some explain why there is such a speed difference: array_map(array($maxHeap, 'insert'), $arrayOfNumbers); # Av...

Is it possible to use array_map in conjunction with str_replace without calling another function to do the str_replace? For example: array_map(str_replace(' ', '-', XXXXX), $myArr);

I have an array-map which I am associng some values into it. After a certain size the returned value is a PersistentHashMap rather than the original PersistentArrayMap. I've read about this behavio...

I have an array of file names in Powershell, and I would like to prepend a path to each of them and get the result in a new array. In C# I could do this using Linq... var files = new string[] { &qu...

I am using array_map function in my php application. I defined the array_map function like this. $ratingID = $this->db->insert_id(); $rated_item_array = array_map(function ($a) { r...

I have an array like this: $a = array('aa', 'bb', 'cc', 'dd'); I want to add the 'rq' string at the beginning of all the elements of the array. Is it possible to do it by calling array_map() on ...

I want to run 3 native functions on the same array: trim, strtoupper and mysql_real_escape_string. Can this be done? Trying to pass an array as a callback like this isn't working: $exclude = arra...

Can someone explain to me why you can't pass a key as reference? Ex: if(is_array($where)){ foreach($where as &$key => &$value){ $key = sec($key); $value = sec($value); } unset($ke...

Suppose I have simple class like: class MyClass { private $_prop; public function getProp() {return $this->_prop;} [....] } Now what I want to do somwhere not in scope of MyClass is to get...

I have a problem when using the trim() function in php. //Suppose the input variable is null. $input = NULL; echo (trim($input)); As shown above, the output of the codes is empty string if the ...