Level 70
May 29, 2022
6
Level 13
Difference between `instance` vs `bind` ?
What is the difference between instance vs bind in container ?
I believe both bind some instance to a another thing...
app()->instance('a', 2);
app()->bind('a', fn() => 2);
dd(app('a')); //2
Level 13
@tisuchi i didnt talk about singleton, it's about "instance" method vs "bind" method
Level 13
bump
Level 75
Singleton gives a single instance. Read over:
2 likes
Level 56
TL;DR;
- use
->bind()when you want to provide just a FQCN (full-qualified class name), or a factory closure, to instruct the container on how to lazily build an instance only when needed. - use
->instance()when you already have an constructed instance and want to instruct the container to provide that particular instance when required.
->instance() and ->singleton() are similar on practice. The difference being that with ->singleton() you can provide a FQCN or a factory closure so the container can lazily build the instance only when needed. But on both cases the container will hold and provide the same instance every time it is required.
Simple Bindings
We can register a binding using the bind method, passing the class or interface name that we wish to register along with a closure that returns an instance of the class
reference: https://laravel.com/docs/9.x/container#simple-bindings
Binding Instances
You may also bind an existing object instance into the container using the instance method. The given instance will always be returned on subsequent calls into the container
reference: https://laravel.com/docs/9.x/container#binding-instances
5 likes
Level 56
based on your example try this:
app()->bind('a', fn() => 2);
app()->instance('b', fn() => 2);
dd(app('a'), app('b'));
app('a') will return 2 just as before.
But app('b') will return a reference to the the closure, because app()->instance(...) assumes the value is already built and you, the developer, only wants the container to hold the value without trying to do anything with it.
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