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Documentation Index

Fetch the complete documentation index at: https://kawax.biz/llms.txt

Use this file to discover all available pages before exploring further.

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What this page covers

This page does not explain how to use collect(). It gives you a map for reading Laravel framework source code. This is for you if you already know Collection methods and now want to understand why the design looks the way it does.

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Historical evolution

The Collection structure was significantly reorganized when LazyCollection was introduced.

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Up to Laravel 5.8

  • Illuminate\Support\Collection
  • Illuminate\Database\Eloquent\Collection (extends Collection)
At this point, LazyCollection, Enumerable, and EnumeratesValues did not exist yet.

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Changes in Laravel 6.0

With the introduction of LazyCollection, Laravel separated common APIs into Enumerable (interface) and EnumeratesValues (trait).

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Current overall structure (Laravel 13)

Reference: laravel/framework v13.x
Current file paths are under src/Illuminate/Collections/*, but the namespace remains Illuminate\\Support. Check both path and namespace when reading source.

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PHPDoc and PHPStan-style generics

PHP itself still has no native generics. Still, Collection-related classes express strong type information through PHPDoc. The main goals are:
  • Accurate IDE autocompletion
  • Better static analysis with PHPStan and Larastan

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Common syntax

/**
 * @template TKey of array-key
 * @template-covariant TValue
 * @implements \Illuminate\Support\Enumerable<TKey, TValue>
 */
class Collection implements Enumerable
{
    /**
     * @use \Illuminate\Support\Traits\EnumeratesValues<TKey, TValue>
     */
    use EnumeratesValues;
}
SyntaxMeaning
@template TKey of array-keyRestricts key type to int|string
@template-covariant TValueTreats value type as covariant (safe narrowing to more specific types)
@implements ...<TKey, TValue>Passes type arguments to the implemented interface
@extends ...<TKey, TModel>Declares type arguments when extending a parent class
@use ...<TKey, TValue>Declares type arguments when applying a trait

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How this looks in Eloquent Collection

/**
 * @template TKey of array-key
 * @template TModel of \Illuminate\Database\Eloquent\Model
 * @extends \Illuminate\Support\Collection<TKey, TModel>
 */
class Collection extends BaseCollection
{
}
Because TValue becomes concrete as TModel, type inference for methods like map() and filter() becomes model-aware.

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1. Start with Enumerable

First, understand the contract. Knowing the method list here makes the rest much faster.

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2. Follow common methods in EnumeratesValues

Most shared logic, including map, filter, and reduce, lives here. Then you only need to read the differences between Collection and LazyCollection.

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3. Compare Collection and LazyCollection

  • Collection: stores arrays and evaluates eagerly
  • LazyCollection: uses Generator and evaluates lazily
Even for methods with the same name, evaluation timing and memory behavior differ.

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4. Finish with Eloquent\Collection

Focus on model-specific extensions such as find, load, and modelKeys. It is easier to understand after you know base Collection.
When deep-diving one method, follow this order: declaration in Enumerable → implementation in EnumeratesValues → override checks in Collection / LazyCollection.
Last modified on April 23, 2026