interface

Interface

Introduction

The interface component provides a set functions to retrieve information about interfaces.

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

Usage

use Psl;
use Psl\Interface;

interface FooInterface {}
interface BarInterface {}

Psl\invariant(true === Interface\defined(FooInterface::class), '"FooInterface" should be defined.');
Psl\invariant(true === Interface\defined(BarInterface::class), '"BarInterface" should be defined.');
Psl\invariant(false === Interface\defined(BazInterface::class), '"BazInterface" should not be defined.');

API

Functions

• [Interface\defined(string $interface_name): bool php]

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

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

  • [$interface_name php]: The name of the interface to check.

  use Psl\Interface;
  use Psl\IO;
  
  interface FooInterface {}
  interface BarInterface {}
  
  Interface\defined(FooInterface::class); // true
  Interface\defined(BarInterface::class); // true
  Interface\defined(BazInterface::class); // false
  Interface\defined(IO\ReadHandleInterface::class); // false

• [Interface\exists(string $interface_name): bool php]

  Checks if the interface with the given name exists.

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

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

  • [$interface_name php]: The name of the interface to check.

    use Psl\Interface;
    use Psl\IO;
  
    interface FooInterface {}
    interface BarInterface {}
  
    Interface\exists(FooInterface::class); // true
    Interface\exists(BarInterface::class); // true
    Interface\exists(BazInterface::class); // false
    Interface\exists(IO\ReadHandleInterface::class); // true