Single Pass Range

Notation

`X`	A type that is a model of Single Pass Range.
`a`	Object of type X.

Description

A range X where boost::range_iterator<X>::type is a model of Single Pass Iterator.

Associated types

Iterator type	`boost::range_iterator<X>::type`	The type of iterator used to iterate through a Range's elements. The iterator's value type is expected to be the Range's value type. A conversion from the iterator type to the `const` iterator type must exist.
Const iterator type	`boost::range_iterator<const X>::type`	A type of iterator that may be used to examine, but not to modify, a Range's elements.

Valid expressions

The following expressions must be valid.

Name	Expression	Return type
Beginning of range	`boost::begin(a)`	`boost::range_iterator<X>::type` if `a` is mutable, `boost::range_iterator<const X>::type` otherwise
End of range	`boost::end(a)`	`boost::range_iterator<X>::type` if `a` is mutable, `boost::range_iterator<const X>::type` otherwise

Expression semantics

Expression	Semantics	Postcondition
`boost::begin(a)`	Returns an iterator pointing to the first element in the Range.	`boost::begin(a)` is either dereferenceable or past-the-end. It is past-the-end if and only if `boost::distance(a) == 0`.
`boost::end(a)`	Returns an iterator pointing one past the last element in the Range.	`boost::end(a)` is past-the-end.

Complexity guarantees

boost::end(a) is at most amortized linear time, boost::begin(a) is amortized constant time. For most practical purposes, one can expect both to be amortized constant time.

Invariants

Valid range	For any Range `a`, `[boost::begin(a),boost::end(a))` is a valid range, that is, `boost::end(a)` is reachable from `boost::begin(a)` in a finite number of increments.
Completeness	An algorithm that iterates through the range `[boost::begin(a),boost::end(a))` will pass through every element of `a`.