C#

Quote:

Hiding the existence of the setter with an interface already protects against unintentional abuse, so I would say that's enough.

0x01AA wrote:

But like in c++ one can cast the interface and have afterwards full access (in c++ this means a dirty const_cast)

Quote:

you do not trust your users then you cannot directly expose the data at all.

public interface IReadOnlySpectrum
{
    double this[int lambda] { get; }
}
public interface IWritableSpectrum : IReadOnlySpectrum
{
    new double this[int lambda] { get; set; }
}
public class Spectrum : IWritableSpectrum {...}

echo off
cd %~dp0

rem The following two path you Need to adjust to your needs
set regasm_tool= "C:\Windows\Microsoft.NET\Framework\v4.0.30319\RegAsm.exe"
set assembly= "C:\YourProject\YourComVisible.dll"

rem unregister previous version
%regasm_tool% %assembly%  /u

rem Register actual Version and create a YourComVisible.tlb
%regasm_tool% %assembly%  /codebase /tlb

pause

public interface ISomething
{
    void SomeMethod();     // Existing method signature.
    void NewMethod();      // New method signature to add. This would be nice but is a breaking change!
}

// Syntax here is arbitrary and not representative
// of any working implementation.

public interface ISomething
{
    void SomeMethod();     // Existing method signature.
}


// Now extend the above interface...
public extension interface ISomethingEx : ISomething
{
    void NewMethod()
    {
        ... some default implementation;
    }
}

public static string WelcomeMessage(object name, object date) 
{
    return string.Format(CultureInfo.CurrentCulture, GetString("WelcomeMessage", "name", "date"), name, date);
}

private static string GetString(string name, params string[] formatterNames)
{
    var value = _resourceManager.GetString(name);

    Debug.Assert(value != null);

    if (formatterNames != null)
    {
        for (var i = 0; i < formatterNames.Length; i++)
        {
            value = value.Replace("{" + formatterNames[i] + "}", "{" + i + "}");
        }
    }

    return value;
}

string s1 = $"A male speaker of Thai will say { Resources.HelloThaiFromMale} as a greeting; a female speaker of Thai will say {Resources.HelloThaiFromFemale} as a greeting.";