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Rails has_and_belongs_to_many migration
...e. From the docs
By default, the name of the join table comes from the union of the
first two arguments provided to create_join_table, in alphabetical
order. To customize the name of the table, provide a :table_name
option:
...
C++ performance challenge: integer to std::string conversion
...; 32) + (k));
}
template <typename T>
std::string itostr(T o) {
union {
char str[16];
unsigned short u2[8];
unsigned u4[4];
unsigned long long u8[2];
};
unsigned v = o < 0 ? ~o + 1 : o;
u8[0] = (ull(v) * 3518437209u) >> 45;
u8[0] ...
What are rvalues, lvalues, xvalues, glvalues, and prvalues?
...of rvalue, i.e. they're the rvalues that aren't xvalues.
Glvalues are the union of xvalues and lvalues in one group, because they do share a lot of properties in common.
So really, it all comes down to xvalues and the need to restrict movement to exactly and only certain places. Those places are ...
Is a `=default` move constructor equivalent to a member-wise move constructor?
... 15 which says:
The implicitly-defined copy/move constructor for a non-union class X
performs a memberwise copy/move of its bases and members. [ Note:
brace-or-equal-initializers of non-static data members are ignored.
See also the example in 12.6.2. —end note ] The order of
initializa...
When do I use a dot, arrow, or double colon to refer to members of a class in C++?
...ked.
The small print:
In C++, types declared as class, struct, or union are considered "of class type". So the above refers to all three of them.
References are, semantically, aliases to objects, so I should have added "or reference to a pointer" to the #3 as well. However, I thought this...
What is the most effective way for float and double comparison?
...vate:
// The data type used to store the actual floating-point number.
union FloatingPointUnion {
RawType value_; // The raw floating-point number.
Bits bits_; // The bits that represent the number.
};
// Converts an integer from the sign-and-magnitude representation to
// t...
Are PDO prepared statements sufficient to prevent SQL injection?
...es, it's searching for a value in name, but imagine the "OR 1=1" part was "UNION SELECT * FROM users". You now control the query, and as such can abuse it...
– ircmaxell
Jan 25 '18 at 20:17
...
Which kind of pointer do I use when?
...covariant return and non-owning. A rewrite might be good if you meant the union rather than intersection. I'd also say that iteration is worth special mention also.
– Ben Voigt
Jan 2 '12 at 23:11
...
Multiple INSERT statements vs. single INSERT with multiple VALUES
...2008 don't seem to be available so instead I had to look at the equivalent UNION ALL construction in SQL Server 2005.
A typical stack trace is below
sqlservr.exe!FastDBCSToUnicode() + 0xac bytes
sqlservr.exe!nls_sqlhilo() + 0x35 bytes
sqlservr.exe!CXVariant::CmpCompareStr() + 0x2b bytes ...
How to generate keyboard events in Python?
...", wintypes.WORD))
class INPUT(ctypes.Structure):
class _INPUT(ctypes.Union):
_fields_ = (("ki", KEYBDINPUT),
("mi", MOUSEINPUT),
("hi", HARDWAREINPUT))
_anonymous_ = ("_input",)
_fields_ = (("type", wintypes.DWORD),
("_i...