Thread: Question about ENUM

hello there,

i have something confused.

if i type this

Code:

 enum days { sun, mon, tue, wed, thu, fri, sat };

then typing ;

Code:

 cout << days(1);

should not result in outputing "mon" ?
when i do this it outputs the number '1' instead of the day behind this number (sun=0, mon=1)

why is that?

No. An enum is just a nice way of representing integer values. You're aliasing sun for 0, mon for 1, etc.

What you would need to do here is have an array of the string values of the days, like this:

Code:

const char * const dayVals[] = { "Sun", "Mon", "Tue", "Wed", "Thu", "Fri", "Sat" };

and then you can use the enum to index into this array to get the name:

Code:

cout << dayVals[mon] << endl; // prints "Mon"

Originally Posted by rags_to_riches

No. An enum is just a nice way of representing integer values. You're aliasing sun for 0, mon for 1, etc.

What you would need to do here is have an array of the string values of the days, like this:

Code:

const char * const dayVals[] = { "Sun", "Mon", "Tue", "Wed", "Thu", "Fri", "Sat" };

and then you can use the enum to index into this array to get the name:

Code:

cout << dayVals[mon] << endl; // prints "Mon"

do i have to cout << dayVals[mon] ?
what if i want to print all the days in a loop, can't it be printed by dayVals[i] for e.g. ?

Originally Posted by Jonathan Yaniv

do i have to cout << dayVals[mon] ?

Yes.

Originally Posted by Jonathan Yaniv

what if i want to print all the days in a loop, can't it be printed by dayVals[i] for e.g. ?

Yup. You can just run a for-loop over your dayVals array and use the loop index to access individual array elements. Beware that this will not work if your enum definition contains "holes", i.e.

Code:

enum Foo
{
    Bar,
    Blah,
    Meep = 34,  // <-- hole! enum values are not contiguous
    Woosh
};

In such a case, your best bet may be writing a function to print enum values:

Code:

void printFoo( Foo enumVal, std::ostream& out )
{
    switch ( enumVal )
    {
    case Bar:
        out << "Bar";
        break;
        
    case Blah:
        out << "Blah";
        break;
        
    case Meep:
        out << "Meep";
        break;
        
    case Woosh:
        out << "Woosh";
        break;
        
    default:
        out << "UNRECOGNIZED Foo enum with integer value " << enumVal << "!";
    }
}