Loopy (PHP Version)

A utility to make common tasks in loops easier and more readable.

Sometimes in a loop, you need to do something only for the first round or the last round. Or the last round only if there are more than two items. Or for any round that is neither the first nor last. You know how it is.

Loopy is a very simple class that provides a few helper methods.

As an example, suppose you have an array of names and you want to convert them into a comma-separated list with "and" before the last name. And suppose you follow the old-school grammar rules in which you use a comma before "and" in a list of three more more items. You can use Loopy like this:

$name_array = ['Matthew', 'Mark', 'Luke', 'John'];
$name_string = '';

// When initializing Loopy, give it the iterable variable so it can count the items.
$l = new Loopy($name_array)

foreach($name_array as $name){
  // If this is NOT the first loop, we need to insert a comma and/or conjunction.
  if($l->not_first){
    if($l->only(2)){
      // If there are only two names, just insert the conjunction.
      $name_string .= ' and ';
    } elseif($l->more_than(2) && $l->not_last){
      // If there are more than two names, but this is not the last one, insert a comma.
      $name_string .= ', ';
    } else {
      // Otherwise, this must be the last item in a list of three or more. Insert comma and conjunction.
      $name_string .= ', and ';
    }
  }
  
  // Concat the name.
  $name_string .= $name;
  
  // At the end of each loop, you must call the next() method to make Loopy update its internal properties.
  $l->next();
}

echo $name_string; // Will produce: "Matthew, Mark, Luke, and John"

You can probably get the gist of Loopy's capabilities by browsing the souce code (it's only 50 lines), but here's a quick reference of available properties and methods.

Properties

i: Integer representing the index number of the current loop (zero-based by default).

count: The total number of items being looped over.

first: Boolean for whether you are in the first iteration of the loop.

not_first: Boolean, opposite of first.

last: Boolean for whether you are in the last iteration of the loop. (first and last are both true when there is only one item.)

not_last: Boolean, opposite of last.

middle: Boolean for whether you are between the first and the last. (This will never be true if only looping over one or two items.)

Methods

__construct($countable, $starting_index = 0): When you intialize Loopy, give it the array or object you are going to loop over so that it can count it and do the math. Optionally, you can specify a starting index other than zero.

only($n): Returns a boolean for whether the total number of items is equal to $n.

more_than($n): Returns a boolean for whether the total number of items is greater than $n.

less_than($n): Returns a boolean for whether the total number of items is less than $n.

next(): This method must be called at the end of each loop to make Loopy update its internal properties and get ready for the next loop.