Reference to unknown namespace Microsoft.Quantum.Intrinsic

[stefante]

Describe the bug
I am following the instructions for the "hello world"program

namespace Quantum.Bell {
open Microsoft.Quantum.Intrinsic;
open Microsoft.Quantum.Canon;

operation HelloQ () : Unit {
    Message("Hello quantum world!");
}

}

on "dotnet run" I always get the same error message

"Reference to unknown namespace Microsoft.Quantum.Intrinsic"

How do I properly reference this namespace? Thanks

[anpaz]

Hi @stefante, can you add more details about the error message? There is typically a code and a line number associated with the error that will give us more information.
Also, can you let us know what version of .net core (dotnet --info) and what OS this is running on?

[stefante]

Hi @anpaz-msft,

Thanks for the reply and your help

I am running dotnet 2.2.301 and Mac OS Mojave 10.14.5

The first messages are:

• Bell.qs(1,23): error QS0001: The namespace body is invalid [/Users....../Bell/Bell.csproj]

• Bell.qs(3,5): error QS0001: Reference to unknown namespace Microsoft.Quantum.Intrinsic [/Users..... /Bell/Bell.csproj]

Bell.csproj was autogenerated and includes the 2 following package references

• PackageReference Include="Microsoft.Quantum.Canon" Version="0.2.1806.3001-preview"
• PackageReference Include="Microsoft.Quantum.Development.Kit" Version="0.2.1806.3001-preview" /

[cgranade]

@stefante: It sounds like your project templates are out-of-date, as we're currently on version 0.8.1907.1701. In particular, the namespace name Microsoft.Quantum.Intrinsic was introduced with Q# version 0.6, such that this error makes sense when using a package reference to version 0.2 of the Quantum Development Kit.

To update, I'd suggest two steps:

Update your project templates to version 0.8

dotnet new -i Microsoft.Quantum.ProjectTemplates::0.8.1907.1701

Migrate your existing Bell.csproj to use 0.8

To migrate existing projects to use 0.8, use the migration notes for 0.6, but with the version number 0.8.1907.1701 instead. In this case, your Bell.csproj file should include the following lines:

<ItemGroup>
    <PackageReference Include="Microsoft.Quantum.Development.Kit" Version="0.8.1907.1701" />
    <PackageReference Include="Microsoft.Quantum.Standard" Version="0.8.1907.1701" />
</ItemGroup>

[cgranade]

Closing the issue, as I believe that the problem was the version mismatch. If you have any additional questions or if there is a bug with the update process, please feel free to reopen the issue or to file a new issue. Thanks for your feedback!