c*******9
发帖数: 6411 | 1 class A {
void f();
};
will there be a default constructor generated for this? |
P********e
发帖数: 2610 | 2 有４个default function 你自己查查
【在 c*******9 的大作中提到】
: class A {
: void f();
: };
: will there be a default constructor generated for this?
|
S**I
发帖数: 15689 | 3 yes; default constructor, copy constructor, assignment constructor and
destructor will be automatically generated if no definition is given.
【在 c*******9 的大作中提到】
: class A {
: void f();
: };
: will there be a default constructor generated for this?
|
c*******9
发帖数: 6411 | 4 so the default construct are empty since there are no data member? |
j***i
发帖数: 1278 | 5 这个情况不需要把
From inside C++ obj model
There are four characteristics(Member Class Object with Default Constructor,
Base Class with Default Constructor,Class with a Virtual Function, Class wi
th a Virtual Base Class) of a class under which the compiler needs to synthe
size a default constructor for classes that declare no constructor at all. T
he Standard refers to these as implicit, nontrivial default constructors. Th
e synthesized constructor fulfills only an implementation need. It does this
by i
【在 c*******9 的大作中提到】
: so the default construct are empty since there are no data member?
|
B*******g
发帖数: 1593 | 6 这段话是针对某些情况下的derived class说的吧？
Constructor,
Class wi
synthe
all. T
constructors. Th
does this
initializin
object. Clas
【在 j***i 的大作中提到】
: 这个情况不需要把
: From inside C++ obj model
: There are four characteristics(Member Class Object with Default Constructor,
: Base Class with Default Constructor,Class with a Virtual Function, Class wi
: th a Virtual Base Class) of a class under which the compiler needs to synthe
: size a default constructor for classes that declare no constructor at all. T
: he Standard refers to these as implicit, nontrivial default constructors. Th
: e synthesized constructor fulfills only an implementation need. It does this
: by i
|
j***i
发帖数: 1278 | 7 不是,genreal case ,
【在 B*******g 的大作中提到】
: 这段话是针对某些情况下的derived class说的吧？
:
: Constructor,
: Class wi
: synthe
: all. T
: constructors. Th
: does this
: initializin
: object. Clas
|
B*******g
发帖数: 1593 | 8 哦 我之前读错了
虽然他说
Clas
ses that do not exhibit these characteristics and that declare no
constructo
r at all are said to have implicit, trivial default constructors. In
practic
e, these trivial default constructors are not synthesized.
那照他的意思所有POD class 都没有default constructor了？
【在 j***i 的大作中提到】
: 不是,genreal case ,
|
c*******t
发帖数: 13 | 9 常见的编译器都是这么干的，对更一般的POD aggregate class也是如此
【在 B*******g 的大作中提到】
: 哦 我之前读错了
: 虽然他说
: Clas
: ses that do not exhibit these characteristics and that declare no
: constructo
: r at all are said to have implicit, trivial default constructors. In
: practic
: e, these trivial default constructors are not synthesized.
: 那照他的意思所有POD class 都没有default constructor了？
|
h*****0
发帖数: 4889 | 10 ctor肯定是存在的，只不过不干事而已。你还是可以调用的。
Constructor,
wi
synthe
T
Th
this
initializin
Clas
【在 j***i 的大作中提到】
: 这个情况不需要把
: From inside C++ obj model
: There are four characteristics(Member Class Object with Default Constructor,
: Base Class with Default Constructor,Class with a Virtual Function, Class wi
: th a Virtual Base Class) of a class under which the compiler needs to synthe
: size a default constructor for classes that declare no constructor at all. T
: he Standard refers to these as implicit, nontrivial default constructors. Th
: e synthesized constructor fulfills only an implementation need. It does this
: by i
|
P********e
发帖数: 2610 | 11 今天刚看了，更正一下
这种叫trivial ctor,通常情况下是不产生的
前面有人说贴了，4种特性是nontrivial的default ctor,干很多事。是一定有的
【在 h*****0 的大作中提到】
: ctor肯定是存在的，只不过不干事而已。你还是可以调用的。
:
: Constructor,
: wi
: synthe
: T
: Th
: this
: initializin
: Clas
|
