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+<?xml version="1.0"?>
+<concept name="InputIterator" category="Iterator"><!--
+Based on concepts from the SGI Standard Template Library documentation:
+Copyright (c) 1996-1999
+Silicon Graphics Computer Systems, Inc.
+
+Copyright (c) 1994
+Hewlett-Packard Company
+--><!--
+Copyright 2000-2001 University of Notre Dame du Lac.
+Copyright 2001-2002 Indiana University.
+Some concepts based on versions from the MTL draft manual and Boost Graph
+and Property Map documentation:
+Copyright (c) Jeremy Siek, Lie-Quan Lee, and Andrew Lumsdaine 2000
+-->
+  <param name="Iter" role="iterator-type"/>
+
+  <use-header name="iterator"/>
+
+  <models-sentence>The iterator type <arg num="1"/> must be a model of <self/>.</models-sentence>
+
+  <description>
+  <para>An input iterator is an iterator that can read through a sequence of
+  values.  It is single-pass (old values of the iterator cannot be
+  re-used), and read-only.</para>
+
+  <para>An input iterator represents a position in a sequence.  Therefore, the
+  iterator can point into the sequence (returning a value when dereferenced
+  and being incrementable), or be off-the-end (and not dereferenceable or
+  incrementable).</para>
+  </description>
+
+  <refines const="no" concept="Assignable"/>
+  <refines const="no" concept="DefaultConstructible"/>
+  <refines const="no" concept="EqualityComparable"/>
+
+  <notation variables="i j">
+    <sample-value>
+      <type name="Iter"/>
+    </sample-value>
+  </notation>
+
+  <associated-type name="value_type">
+    <get-member-type name="value_type">
+      <apply-template name="std::iterator_traits">
+	<type name="Iter"/>
+      </apply-template>
+    </get-member-type>
+    <description><simpara>The value type of the iterator (not necessarily what
+    <code>*i</code> returns)</simpara></description>
+  </associated-type>
+
+  <associated-type name="difference_type">
+    <get-member-type name="difference_type">
+      <apply-template name="std::iterator_traits">
+	<type name="Iter"/>
+      </apply-template>
+    </get-member-type>
+    <description><simpara>The difference type of the iterator</simpara></description>
+  </associated-type>
+
+  <associated-type name="category">
+    <get-member-type name="iterator_category">
+      <apply-template name="std::iterator_traits">
+	<type name="Iter"/>
+      </apply-template>
+    </get-member-type>
+    <description><simpara>The category of the iterator</simpara></description>
+  </associated-type>
+
+  <notation variables="x">
+    <sample-value>
+      <type name="value_type"/>
+    </sample-value>
+  </notation>
+
+  <valid-type-expression name="Category tag">
+    <description/>
+    <type name="category"/>
+    <return-type>
+      <derived-from testable="yes">
+	<type name="std::input_iterator_tag"/>
+      </derived-from>
+      <models-as-first-arg const="no" testable="yes" concept="DefaultConstructible"/>
+      <models-as-first-arg const="no" testable="yes" concept="CopyConstructible"/>
+    </return-type>
+  </valid-type-expression>
+
+  <valid-type-expression name="Value type copy constructibility">
+    <description/>
+    <type name="value_type"/>
+    <return-type>
+      <models-as-first-arg const="no" testable="yes" concept="CopyConstructible"/>
+    </return-type>
+  </valid-type-expression>
+
+  <valid-type-expression name="Difference type properties">
+    <description/>
+    <type name="difference_type"/>
+    <return-type>
+      <models-as-first-arg const="no" testable="yes" concept="SignedInteger"/>
+    </return-type>
+  </valid-type-expression>
+
+  <valid-expression name="Dereference">
+    <dereference>
+      <sample-value><type name="Iter"/></sample-value>
+    </dereference>
+    <return-type>
+      <convertible-to testable="yes"><type name="value_type"/></convertible-to>
+    </return-type>
+    <precondition><code>i</code> is incrementable (not
+    off-the-end)</precondition>
+  </valid-expression>
+
+  <valid-expression name="Preincrement">
+    <preincrement>
+      <sample-value><reference-to><type name="Iter"/></reference-to></sample-value>
+    </preincrement>
+    <return-type>
+      <require-same-type testable="yes">
+	<reference-to><type name="Iter"/></reference-to>
+      </require-same-type>
+    </return-type>
+    <precondition><code>i</code> is incrementable (not
+    off-the-end)</precondition>
+  </valid-expression>
+
+  <valid-expression name="Postincrement">
+    <postincrement>
+      <sample-value><reference-to><type name="Iter"/></reference-to></sample-value>
+    </postincrement>
+    <return-type/>
+    <precondition><code>i</code> is incrementable (not
+    off-the-end)</precondition>
+    <semantics>Equivalent to <code>(void)(++i)</code></semantics>
+    <postcondition><code>i</code> is dereferenceable or
+    off-the-end</postcondition>
+  </valid-expression>
+
+  <valid-expression name="Postincrement and dereference">
+    <dereference>
+      <postincrement>
+	<sample-value><reference-to><type name="Iter"/></reference-to></sample-value>
+      </postincrement>
+    </dereference>
+    <return-type>
+      <convertible-to testable="yes"><type name="value_type"/></convertible-to>
+    </return-type>
+    <precondition><code>i</code> is incrementable (not
+    off-the-end)</precondition>
+    <semantics>Equivalent to <code>{value_type t = *i; ++i; return t;}</code></semantics>
+    <postcondition><code>i</code> is dereferenceable or
+    off-the-end</postcondition>
+  </valid-expression>
+
+  <complexity>
+  All iterator operations must take amortized constant time.
+  </complexity>
+
+  <example-model>
+    <type name="std::istream_iterator"/>
+  </example-model>
+
+  <see-also concept="OutputIterator"/>
+  <see-also concept="ForwardIterator"/>
+
+</concept>