Error in running Examplr project of Teleportation in Q#

Question

I am learning Q# language. I am running the Example of "Teleportation_project" https://learn.microsoft.com/en-us/azure/quantum/user-guide/how-to-work-with-qsharp-projects?tabs=tabid-qsharp%2Ctabid-qsharp-run But when I am running this example I got error. The error comes in the filr PrepareState in which we have a code

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namespace PrepareBell {

operation PrepareBellPair(left : Qubit, right : Qubit) : Unit is Adj + Ctl {

    H(left);

    CNOT(left, right);

}

}

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The error I am getting is that
"entry point not found help: a single callable with the @EntryPoint() attribute must be present if no entry expression is provided(Qsc.EntryPoint.NotFound)". What Can I do that to elemenate the erroe. I debug the code but it also gives the same error. Thank you

Answer 1

Hello, @Razeen ud-Din / PhD Scholar !

Why am I getting an @EntryPoint() error in my Q# code?

The @EntryPoint() attribute tells the Q# compiler where to begin executing the program. In programs with multiple function and operation definitions, the @EntryPoint() can be placed before any of the functions or operations and program flow starts from there and continues sequentially.

If the @EntryPoint() attribute is not included in your Q# code, then you may get the following error:

Entry point not found help: a single callable with the @EntryPoint() attribute must be present if no entry expression is provided(Qsc.EntryPoint.NotFound)

https://learn.microsoft.com/en-us/azure/quantum/user-guide/program-structure#entrypoint

Additional Reading:

• Structure of a Q# program
• Get started with Q# programs and Visual Studio Code

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