trait

Trait

Introduction

The trait component provides a set functions to retrieve information about traits.

!> The Trait component is not a replacement for PHP Reflection API.

Usage

use Psl;
use Psl\Trait;

trait FooTrait {}
trait BarTrait {}

Psl\invariant(true === Trait\defined(FooTrait::class), '"FooTrait" should be defined.');
Psl\invariant(true === Trait\defined(BarTrait::class), '"BarTrait" should be defined.');
Psl\invariant(false === Trait\defined(BazTrait::class), '"BazTrait" should not be defined.');

API

Functions

• [Trait\defined(string $trait_name): bool php]

  Checks if the trait with the given name has already been defined.

  This function will return true if a trait exists, but has not been loaded yet.

  • [$trait_name php]: The name of the trait to check.

  use Psl\Trait;
  use Psl\IO;
  
  trait FooTrait {}
  trait BarTrait {}
  
  Trait\defined(FooTrait::class); // true
  Trait\defined(BarTrait::class); // true
  Trait\defined(BazTrait::class); // false
  Trait\defined(IO\ReadHandleConvenienceMethodsTrait::class); // false

• [Trait\exists(string $trait_name): bool php]

  Checks if the trait with the given name exists.

  If the given trait is not defined, this function will attempt to load it.

  If the given trait is not defined and cannot be loaded, this function will return false.

  • [$trait_name php]: The name of the trait to check.

    use Psl\Trait;
    use Psl\IO;
  
    trait FooTrait {}
    trait BarTrait {}
  
    Trait\exists(FooTrait::class); // true
    Trait\exists(BarTrait::class); // true
    Trait\exists(BazTrait::class); // false
    Trait\exists(IO\ReadHandleConvenienceMethodsTrait::class); // true