original_string: public function register($alias, $class)
  	{
  		$alias = strtolower($alias);
  
  		if (array_key_exists($alias, $this->instances))
  		{
  			throw new \RuntimeException('You cannot register a provider when an instance of that class has already been created.');
  		}
  
  		$this->services[$alias] = $class;
  
  		return $this;
  	}
code: public function register($alias, $class)
  	{
  		$alias = strtolower($alias);
  
  		if (array_key_exists($alias, $this->instances))
  		{
  			throw new \RuntimeException('You cannot register a provider when an instance of that class has already been created.');
  		}
  
  		$this->services[$alias] = $class;
  
  		return $this;
  	}
code_tokens: public function register ( $ alias , $ class ) { $ alias = strtolower ( $ alias ) ; if ( array_key_exists ( $ alias , $ this -> instances ) ) { throw new \ RuntimeException ( 'You cannot register a provider when an instance of that class has already been created.' ) ; } $ this -> services [ $ alias ] = $ class ; return $ this ; }
docstring: Registers a specific class name with the corresponding alias
  for the dependency inversion.
  
  @param $name
  @param $class
  
  @return $this
docstring_tokens: Registers a specific class name with the corresponding alias for the dependency inversion .