Is the C# compiler unable to infer method type parameters by expected return type?
Tag : chash , By : user165781
Date : March 29 2020, 07:55 AM
Hope that helps Check C# Language Specification §7.5.2, the declaring type of a variable is not an attestation for type inference, and obviously it shouldn't be. Consider the following code: Base b = Test<Derived>();
Derived d = Test<Derived>();
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Why doesn't Scala fully infer type parameters when type parameters are nested?
Tag : scala , By : Ian Badcoe
Date : March 29 2020, 07:55 AM
To fix the issue you can do Kipton got close with his higher-kinded solution. Unfortunately he tripped over what appears to be a bug in Scala < 2.9.1.RC1. The following works as expected with 2.9.1.RC1 and trunk, Welcome to Scala version 2.9.1.RC1 (Java HotSpot(TM) Server VM, Java 1.7.0).
Type in expressions to have them evaluated.
Type :help for more information.
scala> abstract class A
defined class A
scala> abstract class B[T <: A]
defined class B
scala> class ConcreteA extends A
defined class ConcreteA
scala> class ConcreteB[T <: A] extends B[T]
defined class ConcreteB
scala> class Example[T <: A, U[X <: A] <: B[X]](resolver: U[T])
defined class Example
scala> new Example(new ConcreteB[ConcreteA])
res0: Example[ConcreteA,ConcreteB] = Example@ec48e7
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parameters with optional closures in swift
Date : March 29 2020, 07:55 AM
hope this fix your issue Firstly, to use closures as an argument for a function, you should declare them like so: func myFunc(closure: (Int) -> Void) {
// Now I can call closure like so:
let myInt = 10
closure(myInt)
}
func myFunc(closure: ((Int) -> Void)?) {
// Now when calling the closure you need to make sure it's not nil.
// For example:
closure?(10)
}
func myFunc(closure: ((Int) -> Void)? = nil) {
// Still need to make sure it's not nil.
if let c = closure {
c(10)
}
}
func myFunc(closure: ((value: Int) -> Void)) {
closure(value: 10)
}
typealias MyClosureType = () -> Void
func myFunc(closure: MyClosureType) {
closure()
}
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Infer teacher-student relationships via courses?
Date : March 29 2020, 07:55 AM
wish help you to fix your issue Is determining that Hechinger is a student of Cadbury something that I should be able to do with OWL reasoning or inference in Protege? @prefix : <urn:ex:#> .
@prefix ex: <urn:ex:#> .
@prefix rdf: <http://www.w3.org/1999/02/22-rdf-syntax-ns#> .
@prefix owl: <http://www.w3.org/2002/07/owl#> .
@prefix xsd: <http://www.w3.org/2001/XMLSchema#> .
@prefix rdfs: <http://www.w3.org/2000/01/rdf-schema#> .
ex:isStudentOf a owl:ObjectProperty ;
owl:propertyChainAxiom ( ex:studies _:b0 ) .
ex:studies a owl:ObjectProperty .
_:b0 owl:inverseOf ex:teaches .
ex:EL101 a owl:Thing , owl:NamedIndividual .
<urn:ex:> a owl:Ontology .
ex:Hechinger a owl:Thing , owl:NamedIndividual ;
ex:studies ex:EL101 .
ex:teaches a owl:ObjectProperty .
ex:Cadbury a owl:Thing , owl:NamedIndividual ;
ex:teaches ex:EL101 .
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Swift closures: Is it possible to specify the return type, without giving up implicit parameters?
Tag : swift , By : Thomas Gueze
Date : March 29 2020, 07:55 AM
To fix this issue Looking into Swift Grammar, specifically the syntax for closure-expression, we can see that closure-parameter-clause is the only required part of closure-signature. Therefore the answer is no. If you want to specify function-result you have to also specify the parameters. let fib: Int = ...
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