src/Plugins/Bindings.php
protected function bindIf($abstract, $concrete = null, $shared = true, $alias = null)
    {
        if ( ! $this->app->bound($abstract)) {
            $concrete = $concrete ?: $abstract;

            $this->app->bind($abstract, $concrete, $shared);
        }
    }
protected function bindIf($abstract, $concrete = null, $shared = true, $alias = null)
    {
        if ( ! $this->app->bound($abstract)) {
            $concrete = $concrete ?: $abstract;

            $this->app->bind($abstract, $concrete, $shared);
        }
    }
protected function bindIf ( $ abstract , $ concrete = null , $ shared = true , $ alias = null ) { if ( ! $ this -> app -> bound ( $ abstract ) ) { $ concrete = $ concrete ? : $ abstract ; $ this -> app -> bind ( $ abstract , $ concrete , $ shared ) ; } }
Registers a binding if it hasn't already been registered.

@param string               $abstract
@param \Closure|string|null $concrete
@param bool                 $shared
@param bool|string|null     $alias
Registers a binding if it hasn t already been registered .