Thread: a trick utterly !

please look at this line below carefully for half a minute:

emun Animal{dog, cat, bird, fish, crocodile};

see it ? OK, when we need some varaibles of Animal we could declare it like this:

PHP Code:

Animal myPet;
myPet=dog; 


and the output of myPet should be a zero. what should it do Though it couldnt be output directly ? Maybe string or Array is much more fit for this occasion. any ideas ?

Originally posted by quagsire

Code:

emun Animal{dog, cat, bird, fish, crocodile}; 
char *AnimalStr[] = {"dog","cat","bird","fish","crocodile"};
Animal myPet;
myPet=dog;
cout << AnimalStr[myPet];

since that, why not use string directly ? it should be more convenient.

Maybe not. Seems to me that comparing simple integers is faster than doing a strcmp every time you need the contents of myPet. Another pro for enumerations is that it's never invalid. When you work with strings you might accidentally type "Dig" instead of dog, the compiler won't warn you and your program won't be able to handle it. It's the same like that with config files that contain a keyset. The keys are all numbered, but a setup program will need to display humanly readable names, so you use an array of strings to go along with it.

Originally posted by Boksha
Maybe not. Seems to me that comparing simple integers is faster than doing a strcmp every time you need the contents of myPet. Another pro for enumerations is that it's never invalid. When you work with strings you might accidentally type "Dig" instead of dog, the compiler won't warn you and your program won't be able to handle it. It's the same like that with config files that contain a keyset. The keys are all numbered, but a setup program will need to display humanly readable names, so you use an array of strings to go along with it.

array could also do, check it below please:

PHP Code:

#include <iostream>
#include <string>

void main()
{
  int i;  // the number stand for different elements.
  string Animal[5]={"dog", "cat", "bird", "fish", "crocodile"}; 
  for(i=0;i<5;i++)
  {
    cout << Animal[i] << endl;
  }
  cin >> "what";
} 


but having a set of enums with it could be usefull in switch case statements


instead of

Code:

switch(type)
{
    case 0:
        dog
    case 1:
        cat
}

this

Code:

switch(type)
{
    case Dog:
        dog
    case Cat:
        cat
}

or for random access

Animal[Dog]

is infinitly more explanitory that

Animal[0]

NOTE: this does not mean you must use the enums in loops and such

it doesn't require the reader to be 100% familiar with every aspect of the code to read it.

its just my opinion though...

Originally posted by no-one
but having a set of enums with it could be usefull in switch case statements...

woh, that's it ! I know just a little about switch so ... It seems I should read something on it, thanx, guys~