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0 pointshota_mazi9y ago0 comments

> First of all, passing parameters in functions is "dependency injection". And what you're describing is a really good thing.

It's only injection if the parameter is passed automatically by a framework. Otherwise, it's parameter passing.

And it's only a good thing if you value referential transparency over ease of testing and encapsulation. Not everybody does (and personally, sometimes I do and sometimes I don't).

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bad_user9y ago

Dude you're mixing up terms. Quoting from https://en.wikipedia.org/wiki/Dependency_injection : "A dependency is an object that can be used (a service). An injection is the passing of a dependency to a dependent object (a client) that would use it". Basically if A depends on B, but A does not initialize B, but is instead receiving it as a parameter from somewhere, then that's dependency injection.

> it's only a good thing if you value referential transparency over ease of testing and encapsulation

I get the feeling that you're mixing up terms again, as you cannot have ease of testing or good encapsulation without referential transparency.

20andup9y ago

"passing parameters in functions is 'dependency injection'"

No, its not.

hota_maziOP9y ago

You're agreeing with me.

I was saying that passing parameters to functions is "dependency passing", not "dependency injection".

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