public function setShared($key, $definition = [])
    {
        $this->_definitions[$key] = $this->formatDefinition($key, $definition);
        $this->_singletons[$key] = null;
        return $this;
    }
public function setShared($key, $definition = [])
    {
        $this->_definitions[$key] = $this->formatDefinition($key, $definition);
        $this->_singletons[$key] = null;
        return $this;
    }
public function setShared ( $ key , $ definition = [ ] ) { $ this -> _definitions [ $ key ] = $ this -> formatDefinition ( $ key , $ definition ) ; $ this -> _singletons [ $ key ] = null ; return $ this ; }
set singleton callback or object

@param string $key key or class name or interface name
@param mixed  $definition

@return static
@see set()
set singleton callback or object