binary_negate<AdaptableBinaryPredicate>
 |
 |
 |
|
| Categories: functors, adaptors |
Component type: type |
Description
Binary_negate is a function object adaptor: it is an
Adaptable Binary Predicate that represents the logical negation
of some other Adaptable Binary Predicate. That is: if f is an
object of class binary_negate<AdaptableBinaryPredicate>, then
there exists an object pred of class AdaptableBinaryPredicate
such that f(x,y) always returns the same value as !pred(x,y).
There is rarely any reason to construct a binary_negate
directly; it is almost always easier to use the helper function not2.
Example
Finds the first character in a string that is neither
' ' nor '\n'.
char str[MAXLEN];
...
const char* wptr = find_if(str, str + MAXLEN,
compose2(not2(logical_or<bool>()),
bind2nd(equal_to<char>(), ' '),
bind2nd(equal_to<char>(), '\n')));
assert(wptr == str + MAXLEN || !(*wptr == ' ' || *wptr == '\n'));
Definition
Defined in the standard header functional, and in the nonstandard
backward-compatibility header function.h.
Template parameters
|
Parameter
|
Description
|
Default
|
|
AdaptableBinaryPredicate
|
The type of the function object that this binary_negate is the logical
negation of.
|
|
Model of
Adaptable Binary Predicate
Type requirements
AdaptableBinaryPredicate must be a model of Adaptable Binary Predicate.
Public base classes
binary_function<AdaptableBinaryPredicate::first_argument_type,
AdaptableBinaryPredicate::second_argument_type,
bool>
Members
New members
These members are not defined in the
Adaptable Binary Predicate
requirements, but are specific to
binary_negate.
|
Member
|
Description
|
binary_negate(const AdaptableBinaryPredicate& pred)
|
The constructor. Creates a binary_negate<AdaptableBinaryPredicate>
whose underlying predicate is pred.
|
template <class AdaptableBinaryPredicate>
binary_negate<AdaptableBinaryPredicate>
not2(const AdaptableBinaryPredicate& pred);
|
If p is of type AdaptableBinaryPredicate then
not2(p) is equivalent to binary_negate<AdaptableBinaryPredicate>(p),
but more convenient. This is a global function, not a member function.
|
Notes
See also
The function object overview, AdaptablePredicate, Predicate,
unary_negate, unary_compose, binary_compose
STL Home