StackOverflow2013

Note that there are some explanatory texts on larger screens.

plurals

PO
primarykey
Id
6549446
data
AcceptedAnswerId
0
AnswerCount
0
ClosedDate
CommentCount
0
CommunityOwnedDate
CreationDate
2011-07-01T14:41:45.233
FavoriteCount
0
LastActivityDate
2011-07-01T14:47:50.237
LastEditDate
2011-07-01T14:47:50.237
LastEditorUserId
76722
OwnerUserId
76722
ParentId
6548075
PostTypeId
2
Score
0
ViewCount
0
LastEditorDisplayName
text
Body
You can (but shouldn't*) use a proxy class that overloads the conversion operators. <h1>Long example with actual usecase *</h1> Let me take my example from <a href="http://ompf.org/forum/viewtopic.php?f=11&t=1453" rel="nofollow">Dot & Cross Product Notation</a>: [...] There is also the possibility of having operator* for both dot-product and cross-product. Assume a basic vector-type (just for demonstration): <pre><code>struct Vector { float x,y,z; Vector() {} Vector (float x, float y, float z) : x(x), y(y), z(z) {} }; </code></pre> We observe that the dot-product is a scalar, the cross-product is a vector. In C++, we may overload conversion operators: <pre><code>struct VecMulRet { public: operator Vector () const { return Vector ( lhs.y*rhs.z - lhs.z*rhs.y, lhs.z*rhs.x - lhs.x*rhs.z, lhs.x*rhs.y - lhs.y*rhs.x ); } operator float () const { return lhs.x*rhs.x + lhs.y*rhs.y + lhs.z*rhs.z; } private: // make construction private and only allow operator* to create an instance Vector const lhs, rhs; VecMulRet (Vector const &lhs, Vector const &rhs) : lhs(lhs), rhs(rhs) {} friend VecMulRet operator * (Vector const &lhs, Vector const &rhs); }; </code></pre> Only operator* is allowed to use struct VecMulRet, copying of VecMulRet is forbidden (paranoia first). Operator* is now defined as follows: <pre><code>VecMulRet operator * (Vector const &lhs, Vector const &rhs) { return VecMulRet (lhs, rhs); } </code></pre> Et voila, we can write: <pre><code>int main () { Vector a,b; float dot = a*b; Vector cross = a*b; } </code></pre> Btw, this is blessed by the Holy Standard as established in 1999. If you read further in that thread, you'll find a benchmark that confirms that this comes at no performance penalty. <h1>Short example for demonstration *</h1> If that was too much to grasp, a more constructed example: <pre><code>struct my_multi_ret { operator unsigned int() const { return 0xdeadbeef; } operator float() const { return 42.f; } }; my_multi_ret multi () { return my_multi_ret(); } #include <iostream> #include <iomanip> int main () { unsigned int i = multi(); float f = multi(); std::cout << std::hex <</pre> <hr> * You can, but shouldn't, because it does not conform to the principle of least surprise as it is not common practice. Still, it is funny.
Tags
Title
singulars
PostAcceptedAnswerId
1. This table or related slice is empty.
PostParentId
1. POCan we declare a function with the same signature but different return type in the base class?
 singulars
 PostTypePostTypeId
 PTQuestion
PostTypePostTypeId
1. PTAnswer
UserLastEditorUserId
1. USSebastian Mach
UserOwnerUserId
1. USSebastian Mach
plurals
PostLinksPostIdRelatedPostId
1. This table or related slice is empty.
PostLinksRelatedPostIdPostId
1. This table or related slice is empty.
PostsAcceptedAnswerId
1. This table or related slice is empty.
PostsParentIdCreationDate
1. This table or related slice is empty.
VotesPostIdCreationDate
1. This table or related slice is empty.
CommentsPostId
1. This table or related slice is empty.

Querying!

Guidance

A row detail

Detail views are divided into sections. All the information in the data section comes from columns in the selected row. The other sections display data from other, related rows.

Related data can be related in a to-one or a to-many fashion. Captions of data related in a to-many fashion link to a list view showing a filtered view of the table.

Try moving around until you find a non-empty to-many entry and click on the label to get to one. You can move back to the root by clicking on the database name in the header.