If you have a class with:
1. Many members
2. Two or more constructors
and if you follow the C++ FAQ guidelines of initializing all member
variables in a contructor initialiazation list, then you might have
two constructors that repeat much of the same code:
MyClass() :
_member1(0),
_member2(0),
_member3("default string")
_member4(0.0)
...etc...
{}
MyClass(int x, int y) :
_member1(0),
_member2(0),
_member3("default string")
_member4(0.0)
...etc...
{
// does some stuff with x and y
}
How can you avoid this unnecessary repetition?
Thanks for any ideas,
cpp 3 1062
"cppaddict" <he***@hello.com> wrote in message
news:56********************************@4ax.com... If you have a class with:
1. Many members
2. Two or more constructors
and if you follow the C++ FAQ guidelines of initializing all member variables in a contructor initialiazation list, then you might have two constructors that repeat much of the same code:
MyClass() : _member1(0), _member2(0), _member3("default string") _member4(0.0) ...etc... {}
MyClass(int x, int y) : _member1(0), _member2(0), _member3("default string") _member4(0.0) ...etc... { // does some stuff with x and y }
How can you avoid this unnecessary repetition?
Thanks for any ideas, cpp
One way is to factor out the common code into another class, usually making
that other class a base class.
class MyClassBase
{
public:
MyClassBase() :
_member1(0),
_member2(0),
_member3("default string")
_member4(0.0)
{
}
protected:
int _member1;
int _member2;
string _member3;
double _member4;
};
class MyClass : public MyClassBase
{
public:
MyClass() {}
MyClass(int x, int y)
{
// do something with x and y
}
};
john
On Sat, 19 Jun 2004 09:22:59 GMT, cppaddict <he***@hello.com> wrote: If you have a class with:
1. Many members
2. Two or more constructors
[]
How can you avoid this unnecessary repetition?
You might like using boost::value_initialized<>. It takes care of member default initialization.
--
Maxim Yegorushkin
On Sat, 19 Jun 2004 09:22:59 +0000, cppaddict wrote: If you have a class with:
1. Many members
2. Two or more constructors
and if you follow the C++ FAQ guidelines of initializing all member variables in a contructor initialiazation list, then you might have two constructors that repeat much of the same code:
MyClass() : _member1(0), _member2(0), _member3("default string") _member4(0.0) ...etc... {}
MyClass(int x, int y) : _member1(0), _member2(0), _member3("default string") _member4(0.0) ...etc... { // does some stuff with x and y }
How can you avoid this unnecessary repetition?
Thanks for any ideas, cpp
Instead of overloading the constructors, You might consider using default
parameters. This may or may not be appropriate, depending on how the
class and the constructors are designed ... This thread has been closed and replies have been disabled. Please start a new discussion. Similar topics
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