mirror of
https://github.com/boostorg/iterator.git
synced 2025-07-24 01:47:17 +02:00
Handled the rest of my issues.
[SVN r21752]
This commit is contained in:
Dave Abrahams
@ -45,43 +45,44 @@ and associated types, to be supplied by a derived iterator class.</td>
|
||||
<div class="contents topic" id="table-of-contents">
|
||||
<p class="topic-title"><a name="table-of-contents">Table of Contents</a></p>
|
||||
<ul class="simple">
|
||||
<li><a class="reference" href="#overview" id="id22" name="id22">Overview</a><ul>
|
||||
<li><a class="reference" href="#usage" id="id23" name="id23">Usage</a></li>
|
||||
<li><a class="reference" href="#iterator-core-access" id="id24" name="id24">Iterator Core Access</a></li>
|
||||
<li><a class="reference" href="#operator" id="id25" name="id25"><tt class="literal"><span class="pre">operator[]</span></tt></a></li>
|
||||
<li><a class="reference" href="#id2" id="id26" name="id26"><tt class="literal"><span class="pre">operator-></span></tt></a></li>
|
||||
<li><a class="reference" href="#overview" id="id23" name="id23">Overview</a><ul>
|
||||
<li><a class="reference" href="#usage" id="id24" name="id24">Usage</a></li>
|
||||
<li><a class="reference" href="#iterator-core-access" id="id25" name="id25">Iterator Core Access</a></li>
|
||||
<li><a class="reference" href="#operator" id="id26" name="id26"><tt class="literal"><span class="pre">operator[]</span></tt></a></li>
|
||||
<li><a class="reference" href="#id2" id="id27" name="id27"><tt class="literal"><span class="pre">operator-></span></tt></a></li>
|
||||
</ul>
|
||||
</li>
|
||||
<li><a class="reference" href="#reference" id="id27" name="id27">Reference</a><ul>
|
||||
<li><a class="reference" href="#iterator-facade-requirements" id="id28" name="id28"><tt class="literal"><span class="pre">iterator_facade</span></tt> Requirements</a></li>
|
||||
<li><a class="reference" href="#iterator-facade-operations" id="id29" name="id29"><tt class="literal"><span class="pre">iterator_facade</span></tt> operations</a></li>
|
||||
<li><a class="reference" href="#reference" id="id28" name="id28">Reference</a><ul>
|
||||
<li><a class="reference" href="#iterator-facade-requirements" id="id29" name="id29"><tt class="literal"><span class="pre">iterator_facade</span></tt> Requirements</a></li>
|
||||
<li><a class="reference" href="#iterator-facade-operations" id="id30" name="id30"><tt class="literal"><span class="pre">iterator_facade</span></tt> operations</a></li>
|
||||
<li><a class="reference" href="#iterator-facade-interoperability" id="id31" name="id31"><tt class="literal"><span class="pre">iterator_facade</span></tt> interoperability</a></li>
|
||||
</ul>
|
||||
</li>
|
||||
<li><a class="reference" href="#tutorial-example" id="id30" name="id30">Tutorial Example</a><ul>
|
||||
<li><a class="reference" href="#the-problem" id="id31" name="id31">The Problem</a></li>
|
||||
<li><a class="reference" href="#a-basic-iterator-using-iterator-facade" id="id32" name="id32">A Basic Iterator Using <tt class="literal"><span class="pre">iterator_facade</span></tt></a><ul>
|
||||
<li><a class="reference" href="#template-arguments-for-iterator-facade" id="id33" name="id33">Template Arguments for <tt class="literal"><span class="pre">iterator_facade</span></tt></a><ul>
|
||||
<li><a class="reference" href="#derived" id="id34" name="id34"><tt class="literal"><span class="pre">Derived</span></tt></a></li>
|
||||
<li><a class="reference" href="#value" id="id35" name="id35"><tt class="literal"><span class="pre">Value</span></tt></a></li>
|
||||
<li><a class="reference" href="#categoryortraversal" id="id36" name="id36"><tt class="literal"><span class="pre">CategoryOrTraversal</span></tt></a></li>
|
||||
<li><a class="reference" href="#id11" id="id37" name="id37"><tt class="literal"><span class="pre">Reference</span></tt></a></li>
|
||||
<li><a class="reference" href="#difference" id="id38" name="id38"><tt class="literal"><span class="pre">Difference</span></tt></a></li>
|
||||
<li><a class="reference" href="#tutorial-example" id="id32" name="id32">Tutorial Example</a><ul>
|
||||
<li><a class="reference" href="#the-problem" id="id33" name="id33">The Problem</a></li>
|
||||
<li><a class="reference" href="#a-basic-iterator-using-iterator-facade" id="id34" name="id34">A Basic Iterator Using <tt class="literal"><span class="pre">iterator_facade</span></tt></a><ul>
|
||||
<li><a class="reference" href="#template-arguments-for-iterator-facade" id="id35" name="id35">Template Arguments for <tt class="literal"><span class="pre">iterator_facade</span></tt></a><ul>
|
||||
<li><a class="reference" href="#derived" id="id36" name="id36"><tt class="literal"><span class="pre">Derived</span></tt></a></li>
|
||||
<li><a class="reference" href="#value" id="id37" name="id37"><tt class="literal"><span class="pre">Value</span></tt></a></li>
|
||||
<li><a class="reference" href="#categoryortraversal" id="id38" name="id38"><tt class="literal"><span class="pre">CategoryOrTraversal</span></tt></a></li>
|
||||
<li><a class="reference" href="#id12" id="id39" name="id39"><tt class="literal"><span class="pre">Reference</span></tt></a></li>
|
||||
<li><a class="reference" href="#difference" id="id40" name="id40"><tt class="literal"><span class="pre">Difference</span></tt></a></li>
|
||||
</ul>
|
||||
</li>
|
||||
<li><a class="reference" href="#constructors-and-data-members" id="id39" name="id39">Constructors and Data Members</a></li>
|
||||
<li><a class="reference" href="#implementing-the-core-operations" id="id40" name="id40">Implementing the Core Operations</a></li>
|
||||
<li><a class="reference" href="#constructors-and-data-members" id="id41" name="id41">Constructors and Data Members</a></li>
|
||||
<li><a class="reference" href="#implementing-the-core-operations" id="id42" name="id42">Implementing the Core Operations</a></li>
|
||||
</ul>
|
||||
</li>
|
||||
<li><a class="reference" href="#a-constant-node-iterator" id="id41" name="id41">A constant <tt class="literal"><span class="pre">node_iterator</span></tt></a></li>
|
||||
<li><a class="reference" href="#interoperability" id="id42" name="id42">Interoperability</a></li>
|
||||
<li><a class="reference" href="#telling-the-truth" id="id43" name="id43">Telling the Truth</a></li>
|
||||
<li><a class="reference" href="#wrap-up" id="id44" name="id44">Wrap Up</a></li>
|
||||
<li><a class="reference" href="#a-constant-node-iterator" id="id43" name="id43">A constant <tt class="literal"><span class="pre">node_iterator</span></tt></a></li>
|
||||
<li><a class="reference" href="#interoperability" id="id44" name="id44">Interoperability</a></li>
|
||||
<li><a class="reference" href="#telling-the-truth" id="id45" name="id45">Telling the Truth</a></li>
|
||||
<li><a class="reference" href="#wrap-up" id="id46" name="id46">Wrap Up</a></li>
|
||||
</ul>
|
||||
</li>
|
||||
</ul>
|
||||
</div>
|
||||
<div class="section" id="overview">
|
||||
<h1><a class="toc-backref" href="#id22" name="overview">Overview</a></h1>
|
||||
<h1><a class="toc-backref" href="#id23" name="overview">Overview</a></h1>
|
||||
<!-- Version 1.1 of this ReStructuredText document corresponds to
|
||||
n1530_, the paper accepted by the LWG for TR1. -->
|
||||
<!-- Copyright David Abrahams, Jeremy Siek, and Thomas Witt 2003. All
|
||||
@ -126,7 +127,7 @@ impossible.</li>
|
||||
</ol>
|
||||
</blockquote>
|
||||
<div class="section" id="usage">
|
||||
<h2><a class="toc-backref" href="#id23" name="usage">Usage</a></h2>
|
||||
<h2><a class="toc-backref" href="#id24" name="usage">Usage</a></h2>
|
||||
<p>The user of <tt class="literal"><span class="pre">iterator_facade</span></tt> derives his iterator class from a
|
||||
specialization of <tt class="literal"><span class="pre">iterator_facade</span></tt> and passes the derived
|
||||
iterator class as <tt class="literal"><span class="pre">iterator_facade</span></tt>'s first template parameter.
|
||||
@ -190,7 +191,7 @@ Iterator or a more-refined iterator concept, a default constructor is
|
||||
required.</p>
|
||||
</div>
|
||||
<div class="section" id="iterator-core-access">
|
||||
<h2><a class="toc-backref" href="#id24" name="iterator-core-access">Iterator Core Access</a></h2>
|
||||
<h2><a class="toc-backref" href="#id25" name="iterator-core-access">Iterator Core Access</a></h2>
|
||||
<p><tt class="literal"><span class="pre">iterator_facade</span></tt> and the operator implementations need to be able
|
||||
to access the core member functions in the derived class. Making the
|
||||
core member functions public would expose an implementation detail to
|
||||
@ -224,7 +225,7 @@ open a safety loophole, as every core member function preserves the
|
||||
invariants of the iterator.</p>
|
||||
</div>
|
||||
<div class="section" id="operator">
|
||||
<h2><a class="toc-backref" href="#id25" name="operator"><tt class="literal"><span class="pre">operator[]</span></tt></a></h2>
|
||||
<h2><a class="toc-backref" href="#id26" name="operator"><tt class="literal"><span class="pre">operator[]</span></tt></a></h2>
|
||||
<p>The indexing operator for a generalized iterator presents special
|
||||
challenges. A random access iterator's <tt class="literal"><span class="pre">operator[]</span></tt> is only
|
||||
required to return something convertible to its <tt class="literal"><span class="pre">value_type</span></tt>.
|
||||
@ -247,7 +248,7 @@ class; it will hide the one supplied by <tt class="literal"><span class="pre">it
|
||||
clients of her iterator.</p>
|
||||
<a class="target" id="operator-arrow" name="operator-arrow"></a></div>
|
||||
<div class="section" id="id2">
|
||||
<h2><a class="toc-backref" href="#id26" name="id2"><tt class="literal"><span class="pre">operator-></span></tt></a></h2>
|
||||
<h2><a class="toc-backref" href="#id27" name="id2"><tt class="literal"><span class="pre">operator-></span></tt></a></h2>
|
||||
<p>The <tt class="literal"><span class="pre">reference</span></tt> type of a readable iterator (and today's input
|
||||
iterator) need not in fact be a reference, so long as it is
|
||||
convertible to the iterator's <tt class="literal"><span class="pre">value_type</span></tt>. When the <tt class="literal"><span class="pre">value_type</span></tt>
|
||||
@ -263,14 +264,14 @@ satisfied by the <tt class="literal"><span class="pre">iterator_facade</span></t
|
||||
<colgroup><col class="label" /><col /></colgroup>
|
||||
<col />
|
||||
<tbody valign="top">
|
||||
<tr><td class="label"><a name="cop95">[Cop95]</a></td><td><em>(<a class="fn-backref" href="#id1">1</a>, <a class="fn-backref" href="#id9">2</a>)</em> [Coplien, 1995] Coplien, J., Curiously Recurring Template
|
||||
<tr><td class="label"><a name="cop95">[Cop95]</a></td><td><em>(<a class="fn-backref" href="#id1">1</a>, <a class="fn-backref" href="#id10">2</a>)</em> [Coplien, 1995] Coplien, J., Curiously Recurring Template
|
||||
Patterns, C++ Report, February 1995, pp. 24-27.</td></tr>
|
||||
</tbody>
|
||||
</table>
|
||||
</div>
|
||||
</div>
|
||||
<div class="section" id="reference">
|
||||
<h1><a class="toc-backref" href="#id27" name="reference">Reference</a></h1>
|
||||
<h1><a class="toc-backref" href="#id28" name="reference">Reference</a></h1>
|
||||
<!-- Version 1.3 of this ReStructuredText document corresponds to
|
||||
n1530_, the paper accepted by the LWG for TR1. -->
|
||||
<!-- Copyright David Abrahams, Jeremy Siek, and Thomas Witt 2003. All
|
||||
@ -306,64 +307,62 @@ public:
|
||||
// Comparison operators
|
||||
template <class Dr1, class V1, class TC1, class R1, class D1,
|
||||
class Dr2, class V2, class TC2, class R2, class D2>
|
||||
typename enable_if_interoperable<Dr1, Dr2, bool>::type // exposition
|
||||
operator ==(iterator_facade<Dr1, V1, TC1, R1, D1> const& lhs,
|
||||
iterator_facade<Dr2, V2, TC2, R2, D2> const& rhs);
|
||||
typename enable_if_interoperable<Dr1,Dr2,bool>::type // exposition
|
||||
operator ==(iterator_facade<Dr1,V1,TC1,R1,D1> const& lhs,
|
||||
iterator_facade<Dr2,V2,TC2,R2,D2> const& rhs);
|
||||
|
||||
template <class Dr1, class V1, class TC1, class R1, class D1,
|
||||
class Dr2, class V2, class TC2, class R2, class D2>
|
||||
typename enable_if_interoperable<Dr1, Dr2, bool>::type
|
||||
operator !=(iterator_facade<Dr1, V1, TC1, R1, D1> const& lhs,
|
||||
iterator_facade<Dr2, V2, TC2, R2, D2> const& rhs);
|
||||
typename enable_if_interoperable<Dr1,Dr2,bool>::type
|
||||
operator !=(iterator_facade<Dr1,V1,TC1,R1,D1> const& lhs,
|
||||
iterator_facade<Dr2,V2,TC2,R2,D2> const& rhs);
|
||||
|
||||
template <class Dr1, class V1, class TC1, class R1, class D1,
|
||||
class Dr2, class V2, class TC2, class R2, class D2>
|
||||
typename enable_if_interoperable<Dr1, Dr2, bool>::type
|
||||
operator <(iterator_facade<Dr1, V1, TC1, R1, D1> const& lhs,
|
||||
iterator_facade<Dr2, V2, TC2, R2, D2> const& rhs);
|
||||
typename enable_if_interoperable<Dr1,Dr2,bool>::type
|
||||
operator <(iterator_facade<Dr1,V1,TC1,R1,D1> const& lhs,
|
||||
iterator_facade<Dr2,V2,TC2,R2,D2> const& rhs);
|
||||
|
||||
template <class Dr1, class V1, class TC1, class R1, class D1,
|
||||
class Dr2, class V2, class TC2, class R2, class D2>
|
||||
typename enable_if_interoperable<Dr1, Dr2, bool>::type
|
||||
operator <=(iterator_facade<Dr1, V1, TC1, R1, D1> const& lhs,
|
||||
iterator_facade<Dr2, V2, TC2, R2, D2> const& rhs);
|
||||
typename enable_if_interoperable<Dr1,Dr2,bool>::type
|
||||
operator <=(iterator_facade<Dr1,V1,TC1,R1,D1> const& lhs,
|
||||
iterator_facade<Dr2,V2,TC2,R2,D2> const& rhs);
|
||||
|
||||
template <class Dr1, class V1, class TC1, class R1, class D1,
|
||||
class Dr2, class V2, class TC2, class R2, class D2>
|
||||
typename enable_if_interoperable<Dr1, Dr2, bool>::type
|
||||
operator >(iterator_facade<Dr1, V1, TC1, R1, D1> const& lhs,
|
||||
iterator_facade<Dr2, V2, TC2, R2, D2> const& rhs);
|
||||
typename enable_if_interoperable<Dr1,Dr2,bool>::type
|
||||
operator >(iterator_facade<Dr1,V1,TC1,R1,D1> const& lhs,
|
||||
iterator_facade<Dr2,V2,TC2,R2,D2> const& rhs);
|
||||
|
||||
template <class Dr1, class V1, class TC1, class R1, class D1,
|
||||
class Dr2, class V2, class TC2, class R2, class D2>
|
||||
typename enable_if_interoperable<Dr1, Dr2, bool>::type
|
||||
operator >=(iterator_facade<Dr1, V1, TC1, R1, D1> const& lhs,
|
||||
iterator_facade<Dr2, V2, TC2, R2, D2> const& rhs);
|
||||
|
||||
template <class Dr1, class V1, class TC1, class R1, class D1,
|
||||
class Dr2, class V2, class TC2, class R2, class D2>
|
||||
typename enable_if_interoperable<Dr1, Dr2, bool>::type
|
||||
operator >=(iterator_facade<Dr1, V1, TC1, R1, D1> const& lhs,
|
||||
iterator_facade<Dr2, V2, TC2, R2, D2> const& rhs);
|
||||
typename enable_if_interoperable<Dr1,Dr2,bool>::type
|
||||
operator >=(iterator_facade<Dr1,V1,TC1,R1,D1> const& lhs,
|
||||
iterator_facade<Dr2,V2,TC2,R2,D2> const& rhs);
|
||||
|
||||
// Iterator difference
|
||||
template <class Dr1, class V1, class TC1, class R1, class D1,
|
||||
class Dr2, class V2, class TC2, class R2, class D2>
|
||||
typename enable_if_interoperable<Dr1, Dr2, bool>::type
|
||||
operator -(iterator_facade<Dr1, V1, TC1, R1, D1> const& lhs,
|
||||
iterator_facade<Dr2, V2, TC2, R2, D2> const& rhs);
|
||||
/* see <a class="reference" href="#minus">below</a> */
|
||||
operator-(iterator_facade<Dr1,V1,TC1,R1,D1> const& lhs,
|
||||
iterator_facade<Dr2,V2,TC2,R2,D2> const& rhs);
|
||||
|
||||
// Iterator addition
|
||||
template <class Derived, class V, class TC, class R, class D>
|
||||
Derived operator+ (iterator_facade<Derived, V, TC, R, D> const&,
|
||||
typename Derived::difference_type n)
|
||||
template <class Dr, class V, class TC, class R, class D>
|
||||
Derived operator+ (iterator_facade<Dr,V,TC,R,D> const&,
|
||||
typename Derived::difference_type n);
|
||||
|
||||
template <class Dr, class V, class TC, class R, class D>
|
||||
Derived operator+ (typename Derived::difference_type n,
|
||||
iterator_facade<Dr,V,TC,R,D> const&);
|
||||
</pre>
|
||||
<a class="target" id="iterator-category" name="iterator-category"></a><p>The <tt class="literal"><span class="pre">iterator_category</span></tt> member of <tt class="literal"><span class="pre">iterator_facade</span></tt> is</p>
|
||||
<pre class="literal-block">
|
||||
<em>iterator-category</em>(CategoryOrTraversal, value_type, reference)
|
||||
</pre>
|
||||
<p>where <em>iterator-category</em> is defined as follows:</p>
|
||||
<a class="target" id="id6" name="id6"></a><pre class="literal-block">
|
||||
<a class="target" id="id7" name="id7"></a><pre class="literal-block">
|
||||
<em>iterator-category</em>(C,R,V) :=
|
||||
if (C is convertible to std::input_iterator_tag
|
||||
|| C is convertible to std::output_iterator_tag
|
||||
@ -440,12 +439,13 @@ struct enable_if_interoperable
|
||||
{};
|
||||
</pre>
|
||||
<div class="section" id="iterator-facade-requirements">
|
||||
<h2><a class="toc-backref" href="#id28" name="iterator-facade-requirements"><tt class="literal"><span class="pre">iterator_facade</span></tt> Requirements</a></h2>
|
||||
<h2><a class="toc-backref" href="#id29" name="iterator-facade-requirements"><tt class="literal"><span class="pre">iterator_facade</span></tt> Requirements</a></h2>
|
||||
<p>The following table describes the typical valid expressions on
|
||||
<tt class="literal"><span class="pre">iterator_facade</span></tt>'s <tt class="literal"><span class="pre">Derived</span></tt> parameter, depending on the
|
||||
iterator concept(s) it will model. The operations in the first
|
||||
column must be made accessible to member functions of class
|
||||
<tt class="literal"><span class="pre">iterator_core_access</span></tt>.</p>
|
||||
<tt class="literal"><span class="pre">iterator_core_access</span></tt>. In addition,
|
||||
<tt class="literal"><span class="pre">static_cast<Derived*>(iterator_facade*)</span></tt> shall be well-formed.</p>
|
||||
<p>In the table below, <tt class="literal"><span class="pre">F</span></tt> is <tt class="literal"><span class="pre">iterator_facade<X,V,C,R,D></span></tt>, <tt class="literal"><span class="pre">a</span></tt> is an
|
||||
object of type <tt class="literal"><span class="pre">X</span></tt>, <tt class="literal"><span class="pre">b</span></tt> and <tt class="literal"><span class="pre">c</span></tt> are objects of type <tt class="literal"><span class="pre">const</span> <span class="pre">X</span></tt>,
|
||||
<tt class="literal"><span class="pre">n</span></tt> is an object of <tt class="literal"><span class="pre">F::difference_type</span></tt>, <tt class="literal"><span class="pre">y</span></tt> is a constant
|
||||
@ -456,10 +456,10 @@ interoperable with <tt class="literal"><span class="pre">X</span></tt>.</p>
|
||||
<p class="topic-title"><tt class="literal"><span class="pre">iterator_facade</span></tt> Core Operations</p>
|
||||
<table border class="table">
|
||||
<colgroup>
|
||||
<col width="19%" />
|
||||
<col width="21%" />
|
||||
<col width="35%" />
|
||||
<col width="25%" />
|
||||
<col width="23%" />
|
||||
<col width="27%" />
|
||||
<col width="29%" />
|
||||
</colgroup>
|
||||
<thead valign="bottom">
|
||||
<tr><th>Expression</th>
|
||||
@ -478,8 +478,9 @@ Iterator</td>
|
||||
</tr>
|
||||
<tr><td><tt class="literal"><span class="pre">c.equal(y)</span></tt></td>
|
||||
<td>convertible to bool</td>
|
||||
<td>true iff <tt class="literal"><span class="pre">c</span></tt> and <tt class="literal"><span class="pre">y</span></tt> refer to the
|
||||
same position.</td>
|
||||
<td>true iff <tt class="literal"><span class="pre">c</span></tt> and <tt class="literal"><span class="pre">y</span></tt>
|
||||
refer to the same
|
||||
position.</td>
|
||||
<td>Single Pass Iterator</td>
|
||||
</tr>
|
||||
<tr><td><tt class="literal"><span class="pre">a.increment()</span></tt></td>
|
||||
@ -502,7 +503,8 @@ Iterator</td>
|
||||
<tr><td><tt class="literal"><span class="pre">c.distance_to(z)</span></tt></td>
|
||||
<td>convertible to
|
||||
<tt class="literal"><span class="pre">F::difference_type</span></tt></td>
|
||||
<td>equivalent to <tt class="literal"><span class="pre">distance(c,</span> <span class="pre">X(z))</span></tt>.</td>
|
||||
<td>equivalent to
|
||||
<tt class="literal"><span class="pre">distance(c,</span> <span class="pre">X(z))</span></tt>.</td>
|
||||
<td>Random Access Traversal
|
||||
Iterator</td>
|
||||
</tr>
|
||||
@ -511,7 +513,7 @@ Iterator</td>
|
||||
</div>
|
||||
</div>
|
||||
<div class="section" id="iterator-facade-operations">
|
||||
<h2><a class="toc-backref" href="#id29" name="iterator-facade-operations"><tt class="literal"><span class="pre">iterator_facade</span></tt> operations</a></h2>
|
||||
<h2><a class="toc-backref" href="#id30" name="iterator-facade-operations"><tt class="literal"><span class="pre">iterator_facade</span></tt> operations</a></h2>
|
||||
<p>The operations in this section are described in terms of operations on
|
||||
the core interface of <tt class="literal"><span class="pre">Derived</span></tt> which may be inaccessible
|
||||
(i.e. private). The implementation should access these operations
|
||||
@ -649,10 +651,156 @@ return tmp -= n;
|
||||
</tr>
|
||||
</tbody>
|
||||
</table>
|
||||
<pre class="literal-block">
|
||||
template <class Dr, class V, class TC, class R, class D>
|
||||
Derived operator+ (iterator_facade<Dr,V,TC,R,D> const&,
|
||||
typename Derived::difference_type n);
|
||||
|
||||
template <class Dr, class V, class TC, class R, class D>
|
||||
Derived operator+ (typename Derived::difference_type n,
|
||||
iterator_facade<Dr,V,TC,R,D> const&);
|
||||
</pre>
|
||||
<table class="field-list" frame="void" rules="none">
|
||||
<col class="field-name" />
|
||||
<col class="field-body" />
|
||||
<tbody valign="top">
|
||||
<tr class="field"><th class="field-name">Effects:</th><td class="field-body"><pre class="first last literal-block">
|
||||
Derived tmp(static_cast<Derived const*>(this));
|
||||
return tmp += n;
|
||||
</pre>
|
||||
</td>
|
||||
</tr>
|
||||
</tbody>
|
||||
</table>
|
||||
</div>
|
||||
<div class="section" id="iterator-facade-interoperability">
|
||||
<h2><a class="toc-backref" href="#id31" name="iterator-facade-interoperability"><tt class="literal"><span class="pre">iterator_facade</span></tt> interoperability</a></h2>
|
||||
<pre class="literal-block">
|
||||
template <class Dr1, class V1, class TC1, class R1, class D1,
|
||||
class Dr2, class V2, class TC2, class R2, class D2>
|
||||
typename enable_if_interoperable<Dr1,Dr2,bool>::type
|
||||
operator ==(iterator_facade<Dr1,V1,TC1,R1,D1> const& lhs,
|
||||
iterator_facade<Dr2,V2,TC2,R2,D2> const& rhs);
|
||||
</pre>
|
||||
<table class="field-list" frame="void" rules="none">
|
||||
<col class="field-name" />
|
||||
<col class="field-body" />
|
||||
<tbody valign="top">
|
||||
<tr class="field"><th class="field-name">Returns:</th><td class="field-body">if <tt class="literal"><span class="pre">is_convertible<Dr2,Dr1>::value</span></tt>, then
|
||||
<tt class="literal"><span class="pre">lhs.equal(rhs)</span></tt>. Otherwise, <tt class="literal"><span class="pre">rhs.equal(lhs)</span></tt>.</td>
|
||||
</tr>
|
||||
</tbody>
|
||||
</table>
|
||||
<pre class="literal-block">
|
||||
template <class Dr1, class V1, class TC1, class R1, class D1,
|
||||
class Dr2, class V2, class TC2, class R2, class D2>
|
||||
typename enable_if_interoperable<Dr1,Dr2,bool>::type
|
||||
operator !=(iterator_facade<Dr1,V1,TC1,R1,D1> const& lhs,
|
||||
iterator_facade<Dr2,V2,TC2,R2,D2> const& rhs);
|
||||
</pre>
|
||||
<table class="field-list" frame="void" rules="none">
|
||||
<col class="field-name" />
|
||||
<col class="field-body" />
|
||||
<tbody valign="top">
|
||||
<tr class="field"><th class="field-name">Returns:</th><td class="field-body">if <tt class="literal"><span class="pre">is_convertible<Dr2,Dr1>::value</span></tt>, then
|
||||
<tt class="literal"><span class="pre">!lhs.equal(rhs)</span></tt>. Otherwise, <tt class="literal"><span class="pre">!rhs.equal(lhs)</span></tt>.</td>
|
||||
</tr>
|
||||
</tbody>
|
||||
</table>
|
||||
<pre class="literal-block">
|
||||
template <class Dr1, class V1, class TC1, class R1, class D1,
|
||||
class Dr2, class V2, class TC2, class R2, class D2>
|
||||
typename enable_if_interoperable<Dr1,Dr2,bool>::type
|
||||
operator <(iterator_facade<Dr1,V1,TC1,R1,D1> const& lhs,
|
||||
iterator_facade<Dr2,V2,TC2,R2,D2> const& rhs);
|
||||
</pre>
|
||||
<table class="field-list" frame="void" rules="none">
|
||||
<col class="field-name" />
|
||||
<col class="field-body" />
|
||||
<tbody valign="top">
|
||||
<tr class="field"><th class="field-name">Returns:</th><td class="field-body">if <tt class="literal"><span class="pre">is_convertible<Dr2,Dr1>::value</span></tt>, then
|
||||
<tt class="literal"><span class="pre">lhs.distance_to(rhs)</span> <span class="pre"><</span> <span class="pre">0</span></tt>. Otherwise, <tt class="literal"><span class="pre">rhs.distance_to(lhs)</span> <span class="pre">></span>
|
||||
<span class="pre">0</span></tt>.</td>
|
||||
</tr>
|
||||
</tbody>
|
||||
</table>
|
||||
<pre class="literal-block">
|
||||
template <class Dr1, class V1, class TC1, class R1, class D1,
|
||||
class Dr2, class V2, class TC2, class R2, class D2>
|
||||
typename enable_if_interoperable<Dr1,Dr2,bool>::type
|
||||
operator <=(iterator_facade<Dr1,V1,TC1,R1,D1> const& lhs,
|
||||
iterator_facade<Dr2,V2,TC2,R2,D2> const& rhs);
|
||||
</pre>
|
||||
<table class="field-list" frame="void" rules="none">
|
||||
<col class="field-name" />
|
||||
<col class="field-body" />
|
||||
<tbody valign="top">
|
||||
<tr class="field"><th class="field-name">Returns:</th><td class="field-body">if <tt class="literal"><span class="pre">is_convertible<Dr2,Dr1>::value</span></tt>, then
|
||||
<tt class="literal"><span class="pre">lhs.distance_to(rhs)</span> <span class="pre"><=</span> <span class="pre">0</span></tt>. Otherwise, <tt class="literal"><span class="pre">rhs.distance_to(lhs)</span>
|
||||
<span class="pre">>=</span> <span class="pre">0</span></tt>.</td>
|
||||
</tr>
|
||||
</tbody>
|
||||
</table>
|
||||
<pre class="literal-block">
|
||||
template <class Dr1, class V1, class TC1, class R1, class D1,
|
||||
class Dr2, class V2, class TC2, class R2, class D2>
|
||||
typename enable_if_interoperable<Dr1,Dr2,bool>::type
|
||||
operator >(iterator_facade<Dr1,V1,TC1,R1,D1> const& lhs,
|
||||
iterator_facade<Dr2,V2,TC2,R2,D2> const& rhs);
|
||||
</pre>
|
||||
<table class="field-list" frame="void" rules="none">
|
||||
<col class="field-name" />
|
||||
<col class="field-body" />
|
||||
<tbody valign="top">
|
||||
<tr class="field"><th class="field-name">Returns:</th><td class="field-body">if <tt class="literal"><span class="pre">is_convertible<Dr2,Dr1>::value</span></tt>, then
|
||||
<tt class="literal"><span class="pre">lhs.distance_to(rhs)</span> <span class="pre">></span> <span class="pre">0</span></tt>. Otherwise,
|
||||
<tt class="literal"><span class="pre">rhs.distance_to(lhs)</span> <span class="pre"><</span> <span class="pre">0</span></tt>.</td>
|
||||
</tr>
|
||||
</tbody>
|
||||
</table>
|
||||
<pre class="literal-block">
|
||||
template <class Dr1, class V1, class TC1, class R1, class D1,
|
||||
class Dr2, class V2, class TC2, class R2, class D2>
|
||||
typename enable_if_interoperable<Dr1,Dr2,bool>::type
|
||||
operator >=(iterator_facade<Dr1,V1,TC1,R1,D1> const& lhs,
|
||||
iterator_facade<Dr2,V2,TC2,R2,D2> const& rhs);
|
||||
</pre>
|
||||
<table class="field-list" frame="void" rules="none">
|
||||
<col class="field-name" />
|
||||
<col class="field-body" />
|
||||
<tbody valign="top">
|
||||
<tr class="field"><th class="field-name">Returns:</th><td class="field-body">if <tt class="literal"><span class="pre">is_convertible<Dr2,Dr1>::value</span></tt>, then
|
||||
<tt class="literal"><span class="pre">lhs.distance_to(rhs)</span> <span class="pre">>=</span> <span class="pre">0</span></tt>. Otherwise,
|
||||
<tt class="literal"><span class="pre">rhs.distance_to(lhs)</span> <span class="pre"><=</span> <span class="pre">0</span></tt>.</td>
|
||||
</tr>
|
||||
</tbody>
|
||||
</table>
|
||||
<a class="target" id="minus" name="minus"></a><pre class="literal-block">
|
||||
template <class Dr1, class V1, class TC1, class R1, class D1,
|
||||
class Dr2, class V2, class TC2, class R2, class D2>
|
||||
typename enable_if_interoperable<Dr1,Dr2,difference_type>::type
|
||||
operator -(iterator_facade<Dr1,V1,TC1,R1,D1> const& lhs,
|
||||
iterator_facade<Dr2,V2,TC2,R2,D2> const& rhs);
|
||||
</pre>
|
||||
<table class="field-list" frame="void" rules="none">
|
||||
<col class="field-name" />
|
||||
<col class="field-body" />
|
||||
<tbody valign="top">
|
||||
<tr class="field"><th class="field-name">Return Type:</th><td class="field-body">if <tt class="literal"><span class="pre">is_convertible<Dr2,Dr1>::value</span></tt>, then <tt class="literal"><span class="pre">difference_type</span></tt> shall be
|
||||
<tt class="literal"><span class="pre">iterator_traits<Dr1>::difference_type</span></tt>. Otherwise,
|
||||
<tt class="literal"><span class="pre">difference_type</span></tt> shall be
|
||||
<tt class="literal"><span class="pre">iterator_traits<Dr2>::difference_type</span></tt>.</td>
|
||||
</tr>
|
||||
<tr class="field"><th class="field-name">Returns:</th><td class="field-body">if <tt class="literal"><span class="pre">is_convertible<Dr2,Dr1>::value</span></tt>, then
|
||||
<tt class="literal"><span class="pre">-lhs.distance_to(rhs)</span></tt>. Otherwise,
|
||||
<tt class="literal"><span class="pre">-rhs.distance_to(lhs)</span></tt>.</td>
|
||||
</tr>
|
||||
</tbody>
|
||||
</table>
|
||||
</div>
|
||||
</div>
|
||||
<div class="section" id="tutorial-example">
|
||||
<h1><a class="toc-backref" href="#id30" name="tutorial-example">Tutorial Example</a></h1>
|
||||
<h1><a class="toc-backref" href="#id32" name="tutorial-example">Tutorial Example</a></h1>
|
||||
<!-- Copyright David Abrahams 2004. Use, modification and distribution is -->
|
||||
<!-- subject to the Boost Software License, Version 1.0. (See accompanying -->
|
||||
<!-- file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt) -->
|
||||
@ -662,7 +810,7 @@ example of a linked list of polymorphic objects. This example was
|
||||
inspired by a <a class="reference" href="http://thread.gmane.org/gmane.comp.lib.boost.user/5100">posting</a> by Keith Macdonald on the <a class="reference" href="../../../more/mailing_lists.htm#users">Boost-Users</a>
|
||||
mailing list.</p>
|
||||
<div class="section" id="the-problem">
|
||||
<h2><a class="toc-backref" href="#id31" name="the-problem">The Problem</a></h2>
|
||||
<h2><a class="toc-backref" href="#id33" name="the-problem">The Problem</a></h2>
|
||||
<p>Say we've written a polymorphic linked list node base class:</p>
|
||||
<pre class="literal-block">
|
||||
# include <iostream>
|
||||
@ -724,7 +872,7 @@ inline std::ostream& operator<<(std::ostream& s, node_base const&a
|
||||
lists.</p>
|
||||
</div>
|
||||
<div class="section" id="a-basic-iterator-using-iterator-facade">
|
||||
<h2><a class="toc-backref" href="#id32" name="a-basic-iterator-using-iterator-facade">A Basic Iterator Using <tt class="literal"><span class="pre">iterator_facade</span></tt></a></h2>
|
||||
<h2><a class="toc-backref" href="#id34" name="a-basic-iterator-using-iterator-facade">A Basic Iterator Using <tt class="literal"><span class="pre">iterator_facade</span></tt></a></h2>
|
||||
<p>We will construct a <tt class="literal"><span class="pre">node_iterator</span></tt> class using inheritance from
|
||||
<tt class="literal"><span class="pre">iterator_facade</span></tt> to implement most of the iterator's operations.</p>
|
||||
<pre class="literal-block">
|
||||
@ -738,24 +886,24 @@ class node_iterator
|
||||
};
|
||||
</pre>
|
||||
<div class="section" id="template-arguments-for-iterator-facade">
|
||||
<h3><a class="toc-backref" href="#id33" name="template-arguments-for-iterator-facade">Template Arguments for <tt class="literal"><span class="pre">iterator_facade</span></tt></a></h3>
|
||||
<h3><a class="toc-backref" href="#id35" name="template-arguments-for-iterator-facade">Template Arguments for <tt class="literal"><span class="pre">iterator_facade</span></tt></a></h3>
|
||||
<p><tt class="literal"><span class="pre">iterator_facade</span></tt> has several template parameters, so we must decide
|
||||
what types to use for the arguments. The parameters are <tt class="literal"><span class="pre">Derived</span></tt>,
|
||||
<tt class="literal"><span class="pre">Value</span></tt>, <tt class="literal"><span class="pre">CategoryOrTraversal</span></tt>, <tt class="literal"><span class="pre">Reference</span></tt>, and <tt class="literal"><span class="pre">Difference</span></tt>.</p>
|
||||
<div class="section" id="derived">
|
||||
<h4><a class="toc-backref" href="#id34" name="derived"><tt class="literal"><span class="pre">Derived</span></tt></a></h4>
|
||||
<h4><a class="toc-backref" href="#id36" name="derived"><tt class="literal"><span class="pre">Derived</span></tt></a></h4>
|
||||
<p>Because <tt class="literal"><span class="pre">iterator_facade</span></tt> is meant to be used with the CRTP
|
||||
<a class="citation-reference" href="#cop95" id="id9" name="id9">[Cop95]</a> the first parameter is the iterator class name itself,
|
||||
<a class="citation-reference" href="#cop95" id="id10" name="id10">[Cop95]</a> the first parameter is the iterator class name itself,
|
||||
<tt class="literal"><span class="pre">node_iterator</span></tt>.</p>
|
||||
</div>
|
||||
<div class="section" id="value">
|
||||
<h4><a class="toc-backref" href="#id35" name="value"><tt class="literal"><span class="pre">Value</span></tt></a></h4>
|
||||
<h4><a class="toc-backref" href="#id37" name="value"><tt class="literal"><span class="pre">Value</span></tt></a></h4>
|
||||
<p>The <tt class="literal"><span class="pre">Value</span></tt> parameter determines the <tt class="literal"><span class="pre">node_iterator</span></tt>'s
|
||||
<tt class="literal"><span class="pre">value_type</span></tt>. In this case, we are iterating over <tt class="literal"><span class="pre">node_base</span></tt>
|
||||
objects, so <tt class="literal"><span class="pre">Value</span></tt> will be <tt class="literal"><span class="pre">node_base</span></tt>.</p>
|
||||
</div>
|
||||
<div class="section" id="categoryortraversal">
|
||||
<h4><a class="toc-backref" href="#id36" name="categoryortraversal"><tt class="literal"><span class="pre">CategoryOrTraversal</span></tt></a></h4>
|
||||
<h4><a class="toc-backref" href="#id38" name="categoryortraversal"><tt class="literal"><span class="pre">CategoryOrTraversal</span></tt></a></h4>
|
||||
<p>Now we have to determine which <a class="reference" href="new-iter-concepts.html#iterator-traversal-concepts-lib-iterator-traversal">iterator traversal concept</a> our
|
||||
<tt class="literal"><span class="pre">node_iterator</span></tt> is going to model. Singly-linked lists only have
|
||||
forward links, so our iterator can't can't be a <a class="reference" href="new-iter-concepts.html#bidirectional-traversal-iterators-lib-bidirectional-traversal-iterators">bidirectional
|
||||
@ -763,19 +911,19 @@ traversal iterator</a>. Our iterator should be able to make multiple
|
||||
passes over the same linked list (unlike, say, an
|
||||
<tt class="literal"><span class="pre">istream_iterator</span></tt> which consumes the stream it traverses), so it
|
||||
must be a <a class="reference" href="new-iter-concepts.html#forward-traversal-iterators-lib-forward-traversal-iterators">forward traversal iterator</a>. Therefore, we'll pass
|
||||
<tt class="literal"><span class="pre">boost::forward_traversal_tag</span></tt> in this position <a class="footnote-reference" href="#category" id="id10" name="id10"><sup>1</sup></a>.</p>
|
||||
<tt class="literal"><span class="pre">boost::forward_traversal_tag</span></tt> in this position <a class="footnote-reference" href="#category" id="id11" name="id11"><sup>1</sup></a>.</p>
|
||||
<table class="footnote" frame="void" id="category" rules="none">
|
||||
<colgroup><col class="label" /><col /></colgroup>
|
||||
<tbody valign="top">
|
||||
<tr><td class="label"><a class="fn-backref" href="#id10" name="category">[1]</a></td><td><tt class="literal"><span class="pre">iterator_facade</span></tt> also supports old-style category
|
||||
<tr><td class="label"><a class="fn-backref" href="#id11" name="category">[1]</a></td><td><tt class="literal"><span class="pre">iterator_facade</span></tt> also supports old-style category
|
||||
tags, so we could have passed <tt class="literal"><span class="pre">std::forward_iterator_tag</span></tt> here;
|
||||
either way, the resulting iterator's <tt class="literal"><span class="pre">iterator_category</span></tt> will
|
||||
end up being <tt class="literal"><span class="pre">std::forward_iterator_tag</span></tt>.</td></tr>
|
||||
</tbody>
|
||||
</table>
|
||||
</div>
|
||||
<div class="section" id="id11">
|
||||
<h4><a class="toc-backref" href="#id37" name="id11"><tt class="literal"><span class="pre">Reference</span></tt></a></h4>
|
||||
<div class="section" id="id12">
|
||||
<h4><a class="toc-backref" href="#id39" name="id12"><tt class="literal"><span class="pre">Reference</span></tt></a></h4>
|
||||
<p>The <tt class="literal"><span class="pre">Reference</span></tt> argument becomes the type returned by
|
||||
<tt class="literal"><span class="pre">node_iterator</span></tt>'s dereference operation, and will also be the
|
||||
same as <tt class="literal"><span class="pre">std::iterator_traits<node_iterator>::reference</span></tt>. The
|
||||
@ -784,7 +932,7 @@ library's default for this parameter is <tt class="literal"><span class="pre">Va
|
||||
type, we can omit this argument, or pass <tt class="literal"><span class="pre">use_default</span></tt>.</p>
|
||||
</div>
|
||||
<div class="section" id="difference">
|
||||
<h4><a class="toc-backref" href="#id38" name="difference"><tt class="literal"><span class="pre">Difference</span></tt></a></h4>
|
||||
<h4><a class="toc-backref" href="#id40" name="difference"><tt class="literal"><span class="pre">Difference</span></tt></a></h4>
|
||||
<p>The <tt class="literal"><span class="pre">Difference</span></tt> argument determines how the distance between
|
||||
two <tt class="literal"><span class="pre">node_iterator</span></tt>s will be measured and will also be the
|
||||
same as <tt class="literal"><span class="pre">std::iterator_traits<node_iterator>::difference_type</span></tt>.
|
||||
@ -811,14 +959,14 @@ class node_iterator
|
||||
</div>
|
||||
</div>
|
||||
<div class="section" id="constructors-and-data-members">
|
||||
<h3><a class="toc-backref" href="#id39" name="constructors-and-data-members">Constructors and Data Members</a></h3>
|
||||
<h3><a class="toc-backref" href="#id41" name="constructors-and-data-members">Constructors and Data Members</a></h3>
|
||||
<p>Next we need to decide how to represent the iterator's position.
|
||||
This representation will take the form of data members, so we'll
|
||||
also need to write constructors to initialize them. The
|
||||
<tt class="literal"><span class="pre">node_iterator</span></tt>'s position is quite naturally represented using
|
||||
a pointer to a <tt class="literal"><span class="pre">node_base</span></tt>. We'll need a constructor to build an
|
||||
iterator from a <tt class="literal"><span class="pre">node_base*</span></tt>, and a default constructor to
|
||||
satisfy the <a class="reference" href="new-iter-concepts.html#forward-traversal-iterators-lib-forward-traversal-iterators">forward traversal iterator</a> requirements <a class="footnote-reference" href="#default" id="id12" name="id12"><sup>2</sup></a>.
|
||||
satisfy the <a class="reference" href="new-iter-concepts.html#forward-traversal-iterators-lib-forward-traversal-iterators">forward traversal iterator</a> requirements <a class="footnote-reference" href="#default" id="id13" name="id13"><sup>2</sup></a>.
|
||||
Our <tt class="literal"><span class="pre">node_iterator</span></tt> then becomes:</p>
|
||||
<pre class="literal-block">
|
||||
# include "node.hpp"
|
||||
@ -848,7 +996,7 @@ class node_iterator
|
||||
<table class="footnote" frame="void" id="default" rules="none">
|
||||
<colgroup><col class="label" /><col /></colgroup>
|
||||
<tbody valign="top">
|
||||
<tr><td class="label"><a class="fn-backref" href="#id12" name="default">[2]</a></td><td>Technically, the C++ standard places almost no
|
||||
<tr><td class="label"><a class="fn-backref" href="#id13" name="default">[2]</a></td><td>Technically, the C++ standard places almost no
|
||||
requirements on a default-constructed iterator, so if we were
|
||||
really concerned with efficiency, we could've written the
|
||||
default constructor to leave <tt class="literal"><span class="pre">m_node</span></tt> uninitialized.</td></tr>
|
||||
@ -856,7 +1004,7 @@ default constructor to leave <tt class="literal"><span class="pre">m_node</span>
|
||||
</table>
|
||||
</div>
|
||||
<div class="section" id="implementing-the-core-operations">
|
||||
<h3><a class="toc-backref" href="#id40" name="implementing-the-core-operations">Implementing the Core Operations</a></h3>
|
||||
<h3><a class="toc-backref" href="#id42" name="implementing-the-core-operations">Implementing the Core Operations</a></h3>
|
||||
<p>The last step is to implement the <a class="reference" href="#core-operations">core operations</a> required by
|
||||
the concepts we want our iterator to model. Referring to the
|
||||
<a class="reference" href="#core-operations">table</a>, we can see that the first three rows are applicable
|
||||
@ -907,7 +1055,7 @@ iterator! For a working example of its use, see <a class="reference" href="../e
|
||||
</div>
|
||||
</div>
|
||||
<div class="section" id="a-constant-node-iterator">
|
||||
<h2><a class="toc-backref" href="#id41" name="a-constant-node-iterator">A constant <tt class="literal"><span class="pre">node_iterator</span></tt></a></h2>
|
||||
<h2><a class="toc-backref" href="#id43" name="a-constant-node-iterator">A constant <tt class="literal"><span class="pre">node_iterator</span></tt></a></h2>
|
||||
<div class="sidebar">
|
||||
<p class="sidebar-title">Constant and Mutable iterators</p>
|
||||
<p>The term <strong>mutable iterator</strong> means an iterator through which
|
||||
@ -1008,7 +1156,7 @@ typedef node_iter<node_base const> node_const_iterator;
|
||||
</pre>
|
||||
</div>
|
||||
<div class="section" id="interoperability">
|
||||
<h2><a class="toc-backref" href="#id42" name="interoperability">Interoperability</a></h2>
|
||||
<h2><a class="toc-backref" href="#id44" name="interoperability">Interoperability</a></h2>
|
||||
<p>Our <tt class="literal"><span class="pre">const_node_iterator</span></tt> works perfectly well on its own, but
|
||||
taken together with <tt class="literal"><span class="pre">node_iterator</span></tt> it doesn't quite meet
|
||||
expectations. For example, we'd like to be able to pass a
|
||||
@ -1020,7 +1168,7 @@ compare them for equality.</p>
|
||||
<p>This expected ability to use two different iterator types together
|
||||
is known as <a class="reference" href="new-iter-concepts.html#interoperable-iterators-lib-interoperable-iterators"><strong>interoperability</strong></a>. Achieving interoperability in
|
||||
our case is as simple as templatizing the <tt class="literal"><span class="pre">equal</span></tt> function and
|
||||
adding a templatized converting constructor <a class="footnote-reference" href="#broken" id="id15" name="id15"><sup>3</sup></a> <a class="footnote-reference" href="#random" id="id16" name="id16"><sup>4</sup></a>:</p>
|
||||
adding a templatized converting constructor <a class="footnote-reference" href="#broken" id="id16" name="id16"><sup>3</sup></a> <a class="footnote-reference" href="#random" id="id17" name="id17"><sup>4</sup></a>:</p>
|
||||
<pre class="literal-block">
|
||||
template <class Value>
|
||||
class node_iter
|
||||
@ -1065,14 +1213,14 @@ typedef impl::node_iterator<node_base const> node_const_iterator;
|
||||
<table class="footnote" frame="void" id="broken" rules="none">
|
||||
<colgroup><col class="label" /><col /></colgroup>
|
||||
<tbody valign="top">
|
||||
<tr><td class="label"><a class="fn-backref" href="#id15" name="broken">[3]</a></td><td>If you're using an older compiler and it can't handle
|
||||
<tr><td class="label"><a class="fn-backref" href="#id16" name="broken">[3]</a></td><td>If you're using an older compiler and it can't handle
|
||||
this example, see the <a class="reference" href="../example/node_iterator2.hpp">example code</a> for workarounds.</td></tr>
|
||||
</tbody>
|
||||
</table>
|
||||
<table class="footnote" frame="void" id="random" rules="none">
|
||||
<colgroup><col class="label" /><col /></colgroup>
|
||||
<tbody valign="top">
|
||||
<tr><td class="label"><a class="fn-backref" href="#id16" name="random">[4]</a></td><td>If <tt class="literal"><span class="pre">node_iterator</span></tt> had been a <a class="reference" href="new-iter-concepts.html#random-access-traversal-iterators-lib-random-access-traversal-iterators">random access
|
||||
<tr><td class="label"><a class="fn-backref" href="#id17" name="random">[4]</a></td><td>If <tt class="literal"><span class="pre">node_iterator</span></tt> had been a <a class="reference" href="new-iter-concepts.html#random-access-traversal-iterators-lib-random-access-traversal-iterators">random access
|
||||
traversal iterator</a>, we'd have had to templatize its
|
||||
<tt class="literal"><span class="pre">distance_to</span></tt> function as well.</td></tr>
|
||||
</tbody>
|
||||
@ -1081,7 +1229,7 @@ traversal iterator</a>, we'd have had to templatize its
|
||||
iterators <a class="reference" href="../example/node_iterator2.cpp">here</a>.</p>
|
||||
</div>
|
||||
<div class="section" id="telling-the-truth">
|
||||
<h2><a class="toc-backref" href="#id43" name="telling-the-truth">Telling the Truth</a></h2>
|
||||
<h2><a class="toc-backref" href="#id45" name="telling-the-truth">Telling the Truth</a></h2>
|
||||
<p>Now <tt class="literal"><span class="pre">node_iterator</span></tt> and <tt class="literal"><span class="pre">node_const_iterator</span></tt> behave exactly as
|
||||
you'd expect... almost. We can compare them and we can convert in
|
||||
one direction: from <tt class="literal"><span class="pre">node_iterator</span></tt> to <tt class="literal"><span class="pre">node_const_iterator</span></tt>.
|
||||
@ -1119,7 +1267,7 @@ appropriate:</p>
|
||||
</pre>
|
||||
</div>
|
||||
<div class="section" id="wrap-up">
|
||||
<h2><a class="toc-backref" href="#id44" name="wrap-up">Wrap Up</a></h2>
|
||||
<h2><a class="toc-backref" href="#id46" name="wrap-up">Wrap Up</a></h2>
|
||||
<p>This concludes our <tt class="literal"><span class="pre">iterator_facade</span></tt> tutorial, but before you
|
||||
stop reading we urge you to take a look at <a class="reference" href="iterator_adaptor.html"><tt class="literal"><span class="pre">iterator_adaptor</span></tt></a>.
|
||||
There's another way to approach writing these iterators which might
|
||||
|
||||
Reference in New Issue
Block a user