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is there a trick to overcome clashing function signatures with different returns values? ```fun TfFi...
# getting-started
e
is there a trick to overcome clashing function signatures with different returns values?
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fun TfFile.cert_request(configure: CertRequest.() -> Unit): CertRequest

fun TfFile.cert_request(configure: CertRequest.() -> Unit): PropertyDelegateProvider<Any?, ReadOnlyProperty<Any?, CertRequest>>
@JvmName
works only for case like 
List<String
and 
List<Int
and 
@OverloadResolutionByLambdaReturnType
only with lambdas returning different values
j
Compiler problems aside, how would you expect people to understand which function is called?
e
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cert_request { }
            val a by cert_request { }
if I make use of delegation or not
j
In the case where you don't use it with 
by
, how do you know which one it is?
e
ok
y
How about implementing an 
operator fun CertRequest.provideDelegate
? Could that do the trick?
e
I played with the 
provideDelegate
, but I didn't have any luck 😕
y
Is there a specific reason why it didn't work? Whenever a property is delegated to a 
CertRequest
the `provideDelegate`method should be called automatically, allowing you to do whatever you want. In fact, you can take the current method which returns a Delegate provider and instead make it return its delegate in 
CertRequest.provideDelegate
You might need to make 
TfFile
a context receiver I guess, but it should work I believe.
e
ok, let's give it a try, why 
CertRequest.provideDelegate
? I need as owner 
TfFile
(I have to add this 
CertRequest
instance to a list inside 
TfFile
)
y
Well, is there different logic between a normal CertRequest and one that's inside a property delegate?
e
no
y
If there is a difference, then you need this:
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context(TfFile)
operator fun CertRequest.provideDelegate(...): ReadOnlyProperty<...> {
    this@TfFile.removeCert(this)
    this@TfFile.addCert(generateNewCert())
    return ReadOnlyProperty<...> {...}
}
Okay then, you don't even need a provide delegate. You can simply have this:
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operator fun CertRequest.getValue(...): CertRequest = this
In other words, CertRequest is used as a delegate that just returns itself! That then allows you to have only one 
TfFile.cert_request
and still have it be used as a delegate when needed
e
I'd like to use the variable name though 
val a by cert_request
, in this case 
a
and save it inside 
CertRequest
thta's why I was using 
provideDelegate
pattern
y
Is CertRequest modifiable after creation? If so:
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operator fun CertRequest.provideDelegate(...): CertRequest= this.apply {
    this.myName = property.name
}
operator fun CertRequest.getValue(...): CertRequest = this
e
I can make it modifiable
y
If you wanna keep it not modifiable though, it is a bit more awkward but you can do something like this:
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context(TfFile)
operator fun CertRequest.provideDelegate(...): CertRequest = this.copy(name = property.name).also {
    this@TfFile.removeCertificate(this)
    this@TfFile.addCertificate(it)
} 
operator fun CertRequest.getValue(...): CertRequest = this
But yes I'd suggest to just make it modifiable to make it easier
e
so, I have the following, how the 
by cert_request
is supposed to call 
CertRequest.provideDelegate
? Because it's always being redirected to 
TfFile.cert_request
did you mean 
val a by CertRequest()
? It works quite good in this way indeed
y
No I meant exactly what is in the gist. Does it not work as expected?
e
wait
no you are right, it works, now I get what you meant: so first 
TfFile.cert_request
is called, and then 
CertRequest.provideDelegate
that's a sweet trick, thanks Youssef metal
y
Yep exactly! No problem at all, glad I could help!
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