logical_and<T>


Category: functors 
Component type: type 
Description
Logical_and<T> is a function object; specifically, it is an
Adaptable Binary Predicate, which means it is a function
object that tests the truth or falsehood of some condition.
If f is an object of class logical_and<T>
and x and y are objects of class T (where T is convertible
to bool) then f(x,y) returns true if and only if both x and
y are true. [1]
Example
Finds the first element in a list that lies in the range from 1 to 10.
list<int> L;
...
list<int>::iterator in_range =
find_if(L.begin(), L.end(),
compose2(logical_and<bool>(),
bind2nd(greater_equal<int>(), 1),
bind2nd(less_equal<int>(), 10)));
assert(in_range == L.end()  (*in_range >= 1 && *in_range <= 10));
Definition
Defined in the standard header functional, and in the nonstandard
backwardcompatibility header function.h.
Template parameters
Parameter

Description

Default

T

The type of logical_and's arguments


Model of
Adaptable Binary Predicate, DefaultConstructible
Type requirements
T must be convertible to bool.
Public base classes
binary_function<T, T, bool>
Members
New members
All of logical_and's members are defined in the
Adaptable Binary Function and Default Constructible
requirements.
Logical_and does not introduce any new members.
Notes
[1]
Logical_and and logical_or are not very useful by themselves.
They are mainly useful because, when combined with the function object
adaptor binary_compose, they perform logical operations on other
function objects.
See also
The function object overview, logical_or, logical_not.
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