logo
down
shadow

Can't use generic type declared at method level for method argument that requires a generic type that's declared somewhe


Can't use generic type declared at method level for method argument that requires a generic type that's declared somewhe

By : user2951458
Date : November 18 2020, 11:13 AM
it fixes the issue My ultimate goal is to have a StateTransitionTable, where the client can create an entry which consists of a mainState and states it can jump to from that main state (stored in an ArrayList). This application, Script, runs on a loop, and the transition table should be somewhat self-operating.
code :
interface State<T extends Script> {

}
public class TransitionTable<T extends Script<?>> {
    private Map<T, StateNode> entries = new HashMap<>()
    private StateNode current, start;

    public T getCurrentState() {
        return current.state;
    }

    public StateNode createNode(T state) {
        StateNode entry = new StateNode(state);
        entries.put(state, entry);

        if (startNode == null) {
            startNode = currentNode = entry;
        }
        return entry;
    }

    public class StateNode {
        private ArrayList<T> nodes = new ArrayList<>();
        private T state;

        private StateNode(T state) {
            this.state = state;
        }

        public StateNode addTransition(T state) {
            nodes.add(state);
            return this;
        }
    }
}
State<DemoScript> start = new StartState();
State<DemoScript> walkToA = new WalkToAState();
State<DemoScript> walkToB = new WalkToBState();
State<DemoScript> dance = new DanceState();

TransitionTable<State<DemoScript>> table = new TransitionTable();
table.createNode(start).addTransition(walkToA).addTransition(walkToB);
table.createNode(dance).addTransition(walkToA).addTransition(walkToB);
table.createNode(walkToA).addTransition(dance);
table.createNode(walkToB).addTransition(dance);

public void loop() {
    table.getCurrentState().process(this, table);
}


Share : facebook icon twitter icon
"using the generic type ....<T> requires 1 type argument and generic multiple constraints and using either

"using the generic type ....<T> requires 1 type argument and generic multiple constraints and using either


By : user1505672
Date : March 29 2020, 07:55 AM
may help you . I am unsure what exactly you want the answer to (maybe you could try summing up your actual questions).
However in the case of using multiple constraint types, the MSDN doc says:
code :
void Foo<T>(T arg)
{
  if (arg is IElement)
  {
    var argAsIElement = arg as IElement;

    // Do something with argAsIElement
  }
  if (arg is HtmlControl)
  {
    var argAsHtmlControl = arg as HtmlControl;

    // Do something with argAsHtmlControl
  }
}
using generic type IProcess<T> requires 1 type argument - How to return generic interface?

using generic type IProcess<T> requires 1 type argument - How to return generic interface?


By : Peter Möller
Date : March 29 2020, 07:55 AM
I wish this help you We try to return IProcess that is a non-generic interface when the only interface that we can see in your code sample is generic - IProcess. The compiler doesn't know how to convert IProcess to IProcess.
One possible solution is to add a non-generic interface and make the generic interface inherit from it:
code :
public interface IProcess
{
    void Process(string id);
}


public interface IProcess<T> : IProcess where T : class
{
}
Type inference question: Generic Method Argument to non-Generic Method

Type inference question: Generic Method Argument to non-Generic Method


By : Mztarichy Khodex
Date : March 29 2020, 07:55 AM
seems to work fine This is not possible as T can be anything (the compiler error actually is cannot convert from 'out T' to 'out string'), not just a string or int.
Just expose the privateFoo overloads as public Foo and be done with it, there is no other way as you can't restrict a generic to string or int (both are sealed, and a generic type constraint needs an interface or non sealed class).
Why is C# unable to infer the generic type argument type from a non-generic static method's signature?

Why is C# unable to infer the generic type argument type from a non-generic static method's signature?


By : DaGamesta
Date : March 29 2020, 07:55 AM
Any of those help In general, a method name will not uniquely identify a unique type Action to which the method group could be assigned. For example, even if there's only one overload of Fred and it takes a single Cat argument, that overload could be assigned not just to an Action, but also to some other types like Action, Action, or Action. While there are some cases where one type substitution would be in every way superior to any alternative, that is not always the case. It's cleaner to define the language to require that the type of delegate be specified, than to have the compiler try to "guess", especially since having the compiler guess would mean that many things which shouldn't be breaking changes, would be (e.g. adding a method overload may render ambiguous a type inference which used to work).
Using the generic type 'System.Collections.Generic.List' requires '1' type argument(s)

Using the generic type 'System.Collections.Generic.List' requires '1' type argument(s)


By : biomary
Date : March 29 2020, 07:55 AM
wish helps you I have an assignment to create a "Tweeter" app in c#, and for some reason I can't get it to do the most simple thing, add items to a list and display them.
Related Posts Related Posts :
  • Passing HttpServletResponse in Spring Boot controller method
  • Failed to load libraries: [netty_tcnative_linux_arm_32, netty_tcnative_linux_arm_32_fedora, netty_tcnative_arm_32, netty
  • How to build a small documents storage?
  • Getting pixel position of a text in an image
  • How do I get a list of Methods called from a Class in Eclipse IDE?
  • Convert string to day of week (not exact date)
  • Unable to understand how rounding is working for decimal digits (Java)
  • How to avoid java.lang.NoSuchMethodError: org.apache.poi.util.IOUtils.copy(Ljava/io/InputStream;Ljava/io/OutputStream;)
  • JTable Renderer not working with RowSorter?
  • From java.util.concurrent.Future<T> to play.libs.F.Promise<T>: How to do that in Java?
  • jUnit tests work in Eclipse, but fail in ant - java.lang.RuntimeException: Stub
  • How do i add a tooltip to existing gwt Textbox?
  • actor replying to non-actor
  • Google Cloud Messaging - server connection
  • Which classes are unmodifiable and cannot be intrumented and is there a way to bypass it?
  • Java & Jersey 1.17: Custom default response headers
  • Java rounding error
  • Setting custom RejectedExecutionHandler for ThreadPoolExecutor after executing some tasks?
  • Arquillian test class variables lose value
  • java.util.ConcurrentModificationException while inserting in ArrayList
  • How to write generic Java API without method Overloading
  • Java Serialization / Deserialization of an ArrayList works only on first program execution
  • Conway's Game of Life's rules dont apply properly
  • call a java method when Click on a html button without using javascript
  • Why does SSLSocketFactory.createSocket returns a Socket instead of SSLSocket?
  • How to schedule a task in Tomcat
  • compare two pdf files (approach) using java
  • What is the use of allowCoreThreadTimeout( ) in ThreadPoolExecutor?
  • Describe the Strategy Design Pattern in Java?
  • MongoDB too many open connections
  • Issue with generate JAXB classes with value constructors
  • Moving from one frame to another in java swing
  • Get a thread by Id
  • how to open front camera and back camera at same time?
  • Messed up with Java Declaration
  • Extracting chart in EXcel as image using java
  • How to get latitude and longitude in Android phone?
  • Do GC pauses and kill -STOP produce the same behavior?
  • Android HTML.ImageGetter Images resized
  • The way to instantiate map<String, List<String>> in Java
  • Java Making objects move while buttons held
  • Androidx Navigation View - `setNavigationItemSelectedListener` Doesn't Work
  • after compiling code JFrame does not appear
  • Netbeans project, JFrames ran from the main JFrame close all JFrames in project
  • Square Retrofit Client: How to enable/disable followRedirects? How to intercept redirect URL?
  • Java Circular Reference - Can’t Compile
  • Mouse click on specific time JAVA
  • android 4 onCreateDialog return type incompatible when overriding
  • Java Implementation of Oracle's DBMS_UTILITY.GET_HASH_VALUE Function
  • javac cannot be run, and furthermore does not seem installed
  • Function to obtain a thread given its ID
  • Java File path to Executable has spaces
  • Minimum Oracle Java VM heap memory setting?
  • Elegant way to create one of a large number of classes
  • Java fx binding styles
  • Summing weights based on string in large file
  • Android ListView setOnItemClickListener not working
  • How is the Java Bootstrap Classloader loaded?
  • Check object is blank
  • Add image between text in JEditorPane
  • shadow
    Privacy Policy - Terms - Contact Us © ourworld-yourmove.org