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Fixed base() to always return const&. Cleaned up iterator_adaptor

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specification of inheritance and base class parameters.


[SVN r21821]
This commit is contained in:
Dave Abrahams
2004-01-18 20:54:59 +00:00
parent 309f741588
commit b6068667c9
20 changed files with 121 additions and 134 deletions
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26
doc/iterator_adaptor.html
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@ -127,13 +127,13 @@ template <
, class Difference = use_default
>
class iterator_adaptor
: public iterator_facade&lt;Derived, <em>V</em>, <em>C</em>, <em>R</em>, <em>D</em>&gt; // see <a class="reference" href="#requirements">details</a>
: public iterator_facade&lt;Derived, <em>V'</em>, <em>C'</em>, <em>R'</em>, <em>D'</em>&gt; // see <a class="reference" href="#base-parameters">details</a>
{
friend class iterator_core_access;
public:
iterator_adaptor();
explicit iterator_adaptor(Base iter);
Base const base() const;
Base const const&amp; base() const;
protected:
Base const&amp; base_reference() const;
Base&amp; base_reference();
@ -161,27 +161,27 @@ class iterator_adaptor
</pre>
<a class="target" id="requirements" name="requirements"></a><div class="section" id="iterator-adaptor-requirements">
<h2><a class="toc-backref" href="#id8" name="iterator-adaptor-requirements"><tt class="literal"><span class="pre">iterator_adaptor</span></tt> requirements</a></h2>
<p>The <tt class="literal"><span class="pre">Derived</span></tt> template argument must be a publicly derived from
<tt class="literal"><span class="pre">iterator_adaptor</span></tt>.</p>
<p>The <tt class="literal"><span class="pre">Base</span></tt> argument shall be Assignable and Copy Constructible.</p>
<p>The <tt class="literal"><span class="pre">Base</span></tt> argument shall be Assignable and Copy
Constructible. In addition,
<tt class="literal"><span class="pre">static_cast&lt;Derived*&gt;(iterator_adaptor*)</span></tt> shall be well-formed.</p>
<a class="target" id="base-parameters" name="base-parameters"></a></div>
<div class="section" id="iterator-adaptor-base-class-parameters">
<h2><a class="toc-backref" href="#id9" name="iterator-adaptor-base-class-parameters"><tt class="literal"><span class="pre">iterator_adaptor</span></tt> base class parameters</a></h2>
<p>The <em>V</em>, <em>C</em>, <em>R</em>, and <em>D</em> parameters of the <tt class="literal"><span class="pre">iterator_facade</span></tt>
<p>The <em>V'</em>, <em>C'</em>, <em>R'</em>, and <em>D'</em> parameters of the <tt class="literal"><span class="pre">iterator_facade</span></tt>
used as a base class in the summary of <tt class="literal"><span class="pre">iterator_adaptor</span></tt>
above are defined as follows:</p>
<pre class="literal-block">
<em>V</em> = if (Value is use_default)
<em>V'</em> = if (Value is use_default)
return iterator_traits&lt;Base&gt;::value_type
else
return Value
<em>C</em> = if (CategoryOrTraversal is use_default)
<em>C'</em> = if (CategoryOrTraversal is use_default)
return iterator_traversal&lt;Base&gt;::type
else
return CategoryOrTraversal
<em>R</em> = if (Reference is use_default)
<em>R'</em> = if (Reference is use_default)
if (Value is use_default)
return iterator_traits&lt;Base&gt;::reference
else
@ -189,7 +189,7 @@ above are defined as follows:</p>
else
return Reference
<em>D</em> = if (Difference is use_default)
<em>D'</em> = if (Difference is use_default)
return iterator_traits&lt;Base&gt;::difference_type
else
return Difference
@ -229,7 +229,7 @@ expression involving <tt class="literal"><span class="pre">Derived</span></tt> i
</tr>
</tbody>
</table>
<p><tt class="literal"><span class="pre">Base</span> <span class="pre">const</span> <span class="pre">base()</span> <span class="pre">const;</span></tt></p>
<p><tt class="literal"><span class="pre">Base</span> <span class="pre">const&amp;</span> <span class="pre">base()</span> <span class="pre">const;</span></tt></p>
<table class="field-list" frame="void" rules="none">
<col class="field-name" />
<col class="field-body" />
@ -238,10 +238,6 @@ expression involving <tt class="literal"><span class="pre">Derived</span></tt> i
</tr>
</tbody>
</table>
<p>[Note: specifying <tt class="literal"><span class="pre">Base</span> <span class="pre">const</span></tt> gives implementations license to
return <tt class="literal"><span class="pre">Base</span> <span class="pre">const&amp;</span></tt> for efficiency's sake. If <tt class="literal"><span class="pre">base()</span></tt>
returned just <tt class="literal"><span class="pre">Base</span></tt>, it would be possible to call non-<tt class="literal"><span class="pre">const</span></tt>
member functions on the result object directly]</p>
</div>
<div class="section" id="iterator-adaptor-protected-member-functions">
<h2><a class="toc-backref" href="#id12" name="iterator-adaptor-protected-member-functions"><tt class="literal"><span class="pre">iterator_adaptor</span></tt> protected member functions</a></h2>