Constructor parameter management

Are you familiar with "fallthrough" constructors? you only specify a given parameter at the appropriate "level" of constructor .
given our object with say, x and y and z:

object(xx,yy,zz) {
  x=xx; y=yy; z=zz
}
object (xx,yy) {
  object(xx,yy,defaultz)
}
object (xx) {
  object(xx,defaulty)
}
object (){
  object(defaultx)
}
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Re: Constructor parameter management by John M. Dlugosz (Monsignor) on Dec 17, 2001 at 21:59 UTC
I'm familiar with the concept of using common code for multiple constructors. It's not really the same thing, but it's used for the same purpose; in fact, it's probably more general. It's difficult to apply to C++ because initialization semantics and syntax are not conducive. However, using an intermediate base class does the trick here. To do the same thing as these declared initial values, you need to derive a new type for each member in question, to arrange it so its default value is exactly what you wanted. —John	[reply]

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Re: Constructor parameter management
by John M. Dlugosz (Monsignor) on Dec 17, 2001 at 21:59 UTC

To do the same thing as these declared initial values, you need to derive a new type for each member in question, to arrange it so its default value is exactly what you wanted.

—John

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