less<T>


Category: functors	Component type: type

Description

Less<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 less<T> and x and y are objects of class T, then f(x,y) returns true if x < y and false otherwise.

Example

Finds the first negative element in a list.

list<int> L;
...
list<int>::iterator first_negative = 
       find_if(L.begin(), L.end(), bind2nd(less<int>(), 0));
assert(first_negative == L.end() || *first_negative < 0);

Definition

Defined in the standard header functional, and in the nonstandard backward-compatibility header function.h.

Template parameters

Parameter	Description	Default
`T`	The type of `less`'s arguments.

Model of

Adaptable Binary Predicate, DefaultConstructible

Type requirements

T is LessThan Comparable.

Public base classes

binary_function<T, T, bool>.

Members

Member	Where defined	Description
`first_argument_type`	Adaptable Binary Predicate	The type of the first argument: `T`
`second_argument_type`	Adaptable Binary Predicate	The type of the second argument: `T`
`result_type`	Adaptable Binary Predicate	The type of the result: `bool`
`less()`	DefaultConstructible	The default constructor.
`bool operator()(const T& x, const T& y)`	Binary Function	Function call operator. The return value is `x < y`.

New members

All of less's members are defined in the Adaptable Binary Predicate and DefaultConstructible requirements. less does not introduce any new members.