bslstl_iteratorutil

Detailed Description

Outline

• Purpose
• Classes
• Description
  • Usage
    • Example 1: Finding the Distance Between Two Random Access Iterators

Purpose

Provide utilities operating on iterators and iterator ranges.

Classes

• bslstl::IteratorUtil:

See also

bslstl_hashtable

Description

This component provides a namespace, bslstl::IteratorUtil, containing utility functions for iterator types. In particular, this component includes a function insertDistance that returns the number of elements that should be accounted for when range-inserting in a container, given a pair of iterator a and b describing a half-open range [a .. b).

Usage

This section illustrates intended use of this component.

Example 1: Finding the Distance Between Two Random Access Iterators

Suppose we want to find the number of elements between two random access iterators.

First, we create an array of integer values and two pointers (which are considered random access iterators) referring to the beginning and end of a range within that array:

int values[] = { 1, 2, 3, 4, 5 };
int *begin = &values[0];
int *end   = &values[3];

Now, we use the IteratorUtil::insertDistance class method to calculate the distance of the open range [begin .. end):

std::size_t distance = IteratorUtil::insertDistance(begin, end);
assert(3 == distance);