For learning purposes, I use csc.exe myprogram.cs shipped with Visual Studio Community (my version 17.3.4) to compile basic C# programs. It mostly works, except when using what appears to be latest language features, for example, array range shorthand array[0..] or element from end shothand array[^1].
For example, when trying to access [^1] element.
Arrays.cs(58,47): error CS0518: Predefined type 'System.Index' is not defined or imported
Arrays.cs(58,47): error CS0656: Missing compiler required member 'System.Index..ctor'
I tried passing -langversion:preview to csc but still not working. Also I was unable to find proper usings for it to work.
Can I somehow get those features to work with basic csc compilation? They worked when I created csproj file and used dotnet build, but doing so was multiple times slower than using just csc. Thanks!
Arrays.cs(58,47): error CS0518: Predefined type 'System.Index' is not defined or imported
Arrays.cs(58,47): error CS0656: Missing compiler required member 'System.Index..ctor'
The compiler uses several types to lower index / range expressions to IL. One of those types is System.Index. This error is the compiler noting that it cannot find that type which is necessary to lower that expression to IL.
This feature was added as a part of netcoreapp3.1 where csc defaults to compiling for .NET Framework applications. These types are not present in the standard set of references you get for .NET Framework hence this is why you get the error.
They worked when I created csproj file and used dotnet build ...
That worked because your project file contained something like the following:
<TargetFramework>net6.0</TargetFramework>
This targeted your application for .NET Core, the build command passed along the standard references for that and those included the System.Index type.
... but doing so was multiple times slower than using just csc.
Building a .NET application involves more than just compiling code. It is finding the correct set of references, building dependencies, compiling and deploying the resulting binaries. It's more work hence it's going to take longer to complete. Multiple times slower is not expected, particularly for repeated executions, but it will take more time that invoking csc, or any ofeth other tools used in build, directly.
Related
We have some dynamic C# code that is compiled and executed at runtime.
Both for versioning (TFS) as well as to find possible syntax errors, intellisense, etc. we have the code in our main solution.
This code should not be in the generated assembly though since it might contain data that is not to be distributed.
Is there any way to get the desired behavior of having it in each compile and also not having it in the generated output?
We do have a TFS-based build system, though it would be good to also have this feature for local compiles on each developer's machine.
I have a C# dll that I need to reference in F#. I can do this fine in a .fs file, but I can't seem to get it to work in an F# script (.fsx) It is strange because in my script, I have no problem referencing F# dlls. I thought C# dlls and F# dlls were essentially the same.
EDIT:
I have two dlls (1) csharp.dll and (2) fsharp.dll built with csharp and fsharp respectively. I reference them with:
#r "bin\Debug\csharp.dll"
#r "bin\Debug\fsharp.dll"
which the compiler recognizes. The line where this occurs looks like this:
let new_object = new fsharp.type(Observable<csharp.type>)
Where I'm creating an object defined in fsharp.dll which takes an observer of a type defined in csharp.dll. When I try to run it in FSharp interactive, I get the following error:
error FS0074: The type referenced through 'csharp.type' is defined in an assembly that is not referenced. You must add a reference to assembly 'csharp'.
The thing that doesn't make sense is that csharp.type had been used successfully in a previous line. But when we introduce the csharp.type with an fsharp.type, I get an error all of a sudden saying the csharp type is missing an assembly reference, even though the problem seems to be with the fsharp.type.
It seems you'll need also refer in the script System.Reactive.dll or wherever the class Observable<T> is defined
#Petr is correct. You need to add all references, and their references.
If you are using Visual Studio, I suggest that you install Visual F# Power Tools. When installed, right-click 'References' under your project and choose to 'Generate references for F# interactive'.
This will generate (and keep updated!) the files
{ProjRoot}/Scripts/load-references.fsx
{ProjRoot}/Scripts/load-project.fsx
So in your F# script (assuming it is in the project root), you just do
#load "Scripts/load-project.fsx"
These generated files should go into your version control of choice.
I work on a project target WP 7.5 and above, I add a packages using the Nuget in VS 2012 which name is Coding4fun(Controls).
After that, the IDE give me a warning,
Warning 1 The predefined type 'System.Tuple' is defined in multiple
assemblies in the global alias; using definition from
'c:\Users\Gao\Documents\Visual Studio
2012\Projects\TFSGit\xicihutong\packages\Coding4Fun.Toolkit.Controls.2.0.5\lib\wp71\Coding4Fun.Toolkit.Controls.dll' C:\Users\Gao\Documents\Visual
Studio 2012\Projects\TFSGit\xicihutong\xicihutong\CSC xicihutong
The app runs OK, but how to solve this warning?
From Compiler Warning (level 1) CS1685
This error occurs when a predefined system type such as System.Tuple
is found in two assemblies. One way this can happen is if you are
referencing mscorlib from two different places, such as trying to run
the.Net Framework versions 1.0 and 1.1 side-by-side.
The compiler will use the definition from only one of the assemblies.
This problem occurs probably System.Tuple is defined in two different assemblies. Probably your Coding4Fun.Toolkit.Controls.dll has too besides mscorlib.dll.
If you want to look them both you can check them;
Get a decompiler like ILSpy or Jetbrains dotPeek.
Add all 3rd party assemblies.
Search for System.Tuple
But how to solve this warning?
You can define your 3rd party assemblies reference some aliases. You can follow in your project
Reference -> Properties -> Aliases ->
And change "global" to something different.
Check out for information extern alias (C# Reference)
Newer version of c4f toolkit has resolved this issue.
So I am having an issue converting an opensource project (SQLite) to use a different build system and now I'm having trouble linking projects. Essentially I have a VCProj file that has a definition like this:
<Tool
Name="VCLinkerTool"
AdditionalOptions="/ASSEMBLYRESOURCE:..\System.Data.SQLite\SQLiteCommand.bmp,System.Data.SQLite.SQLiteCommand.bmp
/ASSEMBLYRESOURCE:..\System.Data.SQLite\SQLiteConnection.bmp,System.Data.SQLite.SQLiteConnection.bmp
/ASSEMBLYRESOURCE:..\System.Data.SQLite\SQLiteDataAdapter.bmp,System.Data.SQLite.SQLiteDataAdapter.bmp"
AdditionalDependencies="..\System.Data.SQLite\bin\System.Data.SQLite.netmodule"
OutputFile="..\bin\System.Data.SQLite.DLL"
GenerateManifest="false"
IgnoreDefaultLibraryNames=""
ModuleDefinitionFile="src\sqlite3.def"
EmbedManagedResourceFile=""
DelayLoadDLLs="advapi32.dll"
RandomizedBaseAddress="1"
DataExecutionPrevention="0"
ImportLibrary=""
KeyFile="..\System.Data.SQLite\System.Data.SQLite.snk"
CLRUnmanagedCodeCheck="true"
/>
And I am unable to properly link the System.Data.SQLite.netmodule due to the following error:
Linking...
4>..\System.Data.SQLite\bin\System.Data.SQLite.netmodule : fatal error LNK1302: only support linking safe .netmodules; unable to link pure .netmodule
And the System.Data.SQLite.netmodule is generated from a C#/.NET project. How is it I can force it to compile with the /clr:safe option since according to MSDN this is the way to fix the issue. The problem is is that I don't know how to compile it with /clr:safe. How is it I can do that in the csproj file or in visual studio somewhere? If I am off base in my attempts to fix this please let me know a better way.
UPDATE:
So I have determined the issue but I'm not sure why it is an issue. So the interop project (the C project which compiles the sqlite code and links) uses the VCLinkerTool to link to the System.Data.SQLite.netmodule. There is then a C# project that creates the System.Data.SQLite.netmodule using the following command (Anything in {} was added to reduce length):
C:\Windows\Microsoft.NET\Framework\v3.5\Csc.exe /noconfig /unsafe- /nowarn:1701,1702 /platform:AnyCPU /errorreport:prompt /doc:..\bin\System.Data.SQLite.XML {DLL REFEERENCFES /debug- /filealign:512 /optimize+ /out:obj\Release\System.Data.SQLite.netmodule {RESOURCES AND CS FILES}
The problem is with the /platform:AnyCPU. In my build it is /platform:x86 and for some reason this causes issues when linking and I'm not sure why but this is what I have narrowed it down to since I can change it to AnyCPU and it will build and link properly. Any insight on this is appreciated.
Ok so I finally narrowed down what the issue was and maybe someone can spread some more light onto why that is but I have a rough idea why. Basically you can't have the VCLinkerTool link to .netmodules that were created targetting the /platform:x86 (and I assume any other variant that isn't AnyCpu. I would assume this has to do with the way that the linking occurs internally when linking the mixed mode dll with a .netmodule. So it looks like for this to work you have to have your C# project compiled with /platorm:AnyCpu.
This may be what you are looking for:
To set this compiler option in Visual Studio
1.
In Solution Explorer, right-click the project name, and then click Properties to open the project Property Pages dialog box.
2.
Select the Configuration Properties folder.
3.
On the General property page, modify the Common Language Runtime support property.
Note
When /clr is enabled in the Property Pages dialog box, compiler option properties that are not compatible with /clr are also adjusted, as required. For example, if /RTC is set and then /clr is enabled, /RTC will be turned off.
Also, when you debug a /clr application, set the Debugger Type property to Mixed or Managed only. For more information, see Project Settings for a C++ Debug Configuration.
For information about how the create a module, see /NOASSEMBLY (Create a MSIL Module).
You would have to edit the CSProj to not use features that cause the code to no longer be safe. These are easy to spot -- anywhere where you're using P/Invoke, or anywhere where there's an unsafe code block, that code is not safe. If any of the code in your assembly is unsafe, the whole assembly gets marked as unsafe.
If you remove the unsafe code the resultant assembly will automatically be safe.
(In the case of SQLite I believe this will be impossible, because SQLite is a C library, which cannot be compiled as safe)
How can a C# program detect it is being compiled under a version of C# that does not contain support for the language features used in that program?
The C# compiler will reject the program, and produce some error message, on encountering the features of the language it does not support. This does not address the issue, which is to state that the program is being compiled with too old a version of the C# compiler, or a C# compiler that does not support the required version of C#
Ideally, it would be as simple as
#if CS_VERSION < 3
#error CSharp 3 or later is required
#end
I don't believe you can do that with a C# file, but if you're using MSBuild then the project/solution tools version number can stop it from being built with an older version of MSBuild.
Can you give the exact context of this? One "human" solution rather than a technical one might be to try compiling the code with all the "old" versions, and create a document with: "If you get an error like this it probably means you're using the wrong version..."
Another option you might want to consider to make that even simpler is to have a single "required features" file. This would be unused by your main app, but ask users to compile that first. If it works, the rest of your build should work. If it doesn't, it's due to using the wrong version. That's likely to produce a smaller range of errors from different versions (in particular it doesn't have the problem that the compiler could list errors from different files in a random order).
According to this list of preprocessor directives, it doesn't seem possible. We usually can tell by using generics (detects 2.0), using auto properties (3.0) or dynamic (4.0)
Easy: The compiler will fail and give you an error if it can't compile the code.
There is no predefined symbol for this; you could create your own symbols and define them in your build script. Note that you can fix the language version at the project level:
Project properties -> Build -> Advanced -> Language Version:
ISO-1 is C# 1.2
ISO-2 is C# 2.0
(maps to the csc /langversion parameter)
But note that this doesn't cover everything - there are a few things that this will let through - particularly in the area of generic type inference. This is only an issue if you need to support old compilers; in which case... test with an old compiler.
For example:
int[] arr1 = { 1, 2, 3, 4, 5 };
string[] arr2 = Array.ConvertAll(arr1, delegate (int i) {return i.ToString();});
This works in .NET 3.5/ISO-2 (pseudo C# 2.0), but doesn't work in .NET 2.0 (proper C# 2.0).
Perhaps you can read the supportedRuntime element:
Then you can define the directive you want based on the supportedRuntime, using CSharpProjectConfigurationProperties3.DefineConstants.
You would create a macro in VS to use this.