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c#enumsmonodevelop

Should the Enum values be unique in the global scope?

I read in The Fundamentals of Programming course that the enum values should be unique, having the following example:

enum color = { red, orange, yellow };
enum fruit = { apple, orange, kiwi}; // error: orange is redefined
int kiwi = 42; // error: kiwi is redefined

I also found the same idea on this question: Two enums have some elements in common, why does this produce an error?

Enum names are in global scope, they need to be unique.

I write C# apps in MonoDevelop on Ubuntu 14.10 and I tried to reproduce this behavior:

using System;

namespace FP
{
    class MainClass
    {
        enum color { red, orange, yellow };
        enum fruit { apple, orange, kiwi}; // error: orange is redefined
        int kiwi = 42; // error: kiwi is redefined
        public static void Main (string[] args)
        {
            Console.WriteLine ("Hello World!");
        }
    }
}

The program above compiled successfully.

Is this a known MonoDevelop behavior or why it was compiled without errors? Should the Enum values be unique in the global scope?

Solution

  • What you are talking about is behaviour of the c language.

    In c# enums are not globally accessible by name, you always have to access them by typeName.valueName, e.g. color.Orange, fruit.Orange. So there will be no conflict. In fact many in-built enums use the same value names (StringSplitOptions.None, CompareOptions.None).