Summation Collection

A collection of numeric values, which are typically a product of processing multiple items, e.g. database records. Most commonly, you would use this component in combination with an Items Processor.

Within this context, the term "summation" is referred to as a "[...] cumulative action or effect [...]" (Merriam Webster).

• Basic Example
• Setting initial values
• Processing values
  • Increase
  • Decrease
  • Multiply
  • Divide
  • Apply Callback
• Dot notation
• Determine keys and values
  • Has key
  • Has value
• Removing keys
• Exporting
  • To Array
  • To Json
• Debugging

Basic Example

use Aedart\Collections\Summation;

$collection = Summation::make([
    'points' => 0
]);

$result = $collection
    ->increase('points', 5)
    ->decrease('points', 1)
    ->get('points');

echo $result; // 4

Setting initial values

To work with a Summation collection, you must first set the initial value(s), which you later wish to process in some way. You can either state them when you create a new instance (e.g. via the make() method), or by using the set() method.

$collection = Summation::make([
    'strength' => 15,
    'agility' => 22,
    'intelligence' => 19,
]);

// Or...

$collection = Summation::make()
    ->set('strength', 15)
    ->set('agility', 22)
    ->set('intelligence', 19);

Processing values

Increase

Use the increase() or add() method to increase a key's value with a given amount.

$result = Summation::make()
    ->set('points', 0)
    
    ->increase('points', 5)
    ->add('points', 1)
    
    ->get('points');

echo $result; // 6

Decrease

To decrease a key's value, you can use the decrease() or subtract() method.

$result = Summation::make()
    ->set('points', 25)
    
    ->decrease('points', 5)
    ->subtract('points', 1)
    
    ->get('points');

echo $result; // 19

Multiply

You can multiple an existing key's value using the multiply() method.

$result = Summation::make()
    ->set('points', 5)
    
    ->multiply('points', 5)
    
    ->get('points');

echo $result; // 25

Divide

To divide and existing key's value, use the divide() method.

$result = Summation::make()
    ->set('points', 25)
    
    ->divide('points', 3)
    
    ->get('points');

echo $result; // 8.3333

Apply Callback

All processing methods accept a callable as a value, in which you can process a given key's value, however you want. The result of the given callback is the used as the key's new value.

$result = Summation::make()
    ->set('points', 25)
    ->set('amount', 8)
    
    ->set('points', function($value, Summation $summation) {
        return $value / $summation->get('amount');
    })
    
    ->get('points');

echo $result; // 3.125

Dot notation

Laravel's "dot notation" is also supported by the Summation collection component.

$result = Summation::make()
    ->set('player.strength', 16)
    
    ->increase('player.strength', 2)
    
    ->get('player.strength');

echo $result; // 18

Determine keys and values

Has key

The has() method can be used to determine whether a key exists in the collection or not.

$collection->has('score'); // true or false

Note

The has() will return true if a key exists, even if the key's value is zero (empty).

Has value

To determine if a key exists and has a value (nonempty value), use the hasValue() method.

$collection->hasValue('score'); // true if key exists and has a nonempty value

Removing keys

A key and it's associated value can be deleted by using the remove() method.

$collection->remove('player.intelligence');

Exporting

To Array

The toArray() method will export all keys and values to a native php array.

$arr = $collection->toArray();

To Json

If you wish to retrieve a Json representation of the collection, you can either use the toJson() method or invoke json_encode() directly on the collection.

$result = $collection->toJson();

// Or...

$result = json_encode($collection);

Debugging

Prerequisite

To use the debugging methods, you must have symfony/var-dumper installed.

The dd() method will dump the collection's keys and values and stop further script execution.

$collection->dd(); // Dumps keys and values and STOPS script execution!

The dump() method, on the other hand, will only dump the collection's keys and values.

$result = $collection
    ->set('points', 5)
    ->increase('points', 1)
    ->dump() // Dumps keys and values
    ->decrease('points', 2)
    ->get('points');

echo $result; // 4