2.4 KiB
2.4 KiB
ext-collections
1. Introduction
This PHP extension provides a set of useful functional-style operations on PHP arrays, which makes array manipulation simple and scalable.
Method names and functionalities are inspired by Kotlin.Collections.
1.1 Notes
- Requires PHP 7.1 and above.
- Thread safety:
- Distinct objects: safe.
- Shared objects: unsafe.
2. Documentation
2.1 Functionalities
See stubs directory for signature of all classes and methods of this extension, with PHPDoc. They can also serve as IDE helper.
2.2 PHP-style access
The Collection
class implements ArrayAccess
and Countable
interface internally, you can treat an instance of Collection
as an ArrayObject
.
- The
isset()
,unset()
keywords can be used on elements ofCollection
. - Elements can be accessed via property and bracket expression.
empty()
,count()
can be used on instance ofCollection
.- Elements can be traversed via
foreach()
keyword.
2.4 Notes
- The
Collection::xxxTo()
methods will preserve the original key-value pairs of destinationCollection
when keys collide. - Some methods of
Collection
involves comparing two of its elements, which accepts$flags
as one of its arguments. When these methods are being invoked, make sure all elements are of the same type (numeric/string/others), otherwise you're likely to get a segfault.
3. Example
Here is a simple example for how to work with arrays gracefully using this extension.
$employees = [
['name' => 'Alice', 'sex' => 'female', 'age' => 35],
['name' => 'Bob', 'sex' => 'male', 'age' => 29],
['name' => 'David', 'sex' => 'male', 'age' => 40],
['name' => 'Benjamin', 'sex' => 'male', 'age' => 32]
];
// Trying to get an array of names of male employees,
// sorted by the descending order of their age.
$names = Collection::init($employees)
->filter(function ($value) {
return $value['sex'] == 'male';
})
->sortedByDescending(function ($value) {
return $value['age'];
})
->map(function ($value) {
return $value['name'];
})
->toArray();
// You got $names == ['David', 'Benjamin', 'Bob'].