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<title>Issue 2131: Member function getline taking a string as parameter</title>
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<p><em>This page is a snapshot from the LWG issues list, see the <a href="lwg-active.html">Library Active Issues List</a> for more information and the meaning of <a href="lwg-active.html#NAD">NAD</a> status.</em></p>
<h3 id="2131"><a href="lwg-closed.html#2131">2131</a>. Member function getline taking a string as parameter</h3>
<p><b>Section:</b> 31.7.5.4 <a href="https://wg21.link/istream.unformatted">[istream.unformatted]</a> <b>Status:</b> <a href="lwg-active.html#NAD">NAD</a>
 <b>Submitter:</b> Lo&iuml;c Joly <b>Opened:</b> 2012-03-05 <b>Last modified:</b> 2016-01-28</p>
<p><b>Priority: </b>Not Prioritized
</p>
<p><b>View all other</b> <a href="lwg-index.html#istream.unformatted">issues</a> in [istream.unformatted].</p>
<p><b>View all issues with</b> <a href="lwg-status.html#NAD">NAD</a> status.</p>
<p><b>Discussion:</b></p>
<p>
I think the following code should be legal:
</p>
<blockquote><pre>
void f(std::istream&amp; is)
{
  std::string s;
  is.getline(s); // Would be equivalent to std::getline(is, s)
}
</pre></blockquote>

<p><i>[2013-04-20, Bristol]</i></p>


<p>
Unanimous that this is a new feature request and not a issue. 
<p/>
Resolution: Tentatively NAD 
</p>


<p id="res-2131"><b>Proposed resolution:</b></p>
<p>This wording is relative to N3376.</p>

<ol>
<li><p>Change the class template <code>basic_istream</code> synopsis, 31.7.5.2 <a href="https://wg21.link/istream">[istream]</a>, as indicated</p>
<blockquote><pre>
namespace std {
  template &lt;class charT, class traits = char_traits&lt;charT&gt; &gt;
  class basic_istream : virtual public basic_ios&lt;charT,traits&gt; {
  public:
    [&hellip;]
    <i>// 27.7.2.3 Unformatted input:</i>
    [&hellip;]
    basic_istream&lt;charT,traits&gt;&amp; getline(char_type* s, streamsize n);
    basic_istream&lt;charT,traits&gt;&amp; getline(char_type* s, streamsize n,
      char_type delim);
    <ins>template&lt;class Allocator&gt;
    basic_istream&lt;charT,traits&gt;&amp; getline(basic_string&lt;charT,traits,Allocator&gt;&amp; str);
    template&lt;class Allocator&gt;
    basic_istream&lt;charT,traits&gt;&amp; getline(basic_string&lt;charT,traits,Allocator&gt;&amp; str,
      char_type delim);</ins>
    [&hellip;]
  };
}
</pre></blockquote>
</li>

<li><p>Insert the following two new prototype descriptions after 31.7.5.4 <a href="https://wg21.link/istream.unformatted">[istream.unformatted]</a> paragraph 24:</p>

<blockquote>
<pre>
basic_istream&lt;charT,traits&gt;&amp; getline(char_type* s, streamsize n);
</pre>
<blockquote><p>
-24- <i>Returns</i>: <code>getline(s,n,widen('\n'))</code>
</p>
</blockquote>

<pre>
<ins>template&lt;class Allocator&gt;
basic_istream&lt;charT,traits&gt;&amp; getline(basic_string&lt;charT,traits,Allocator&gt;&amp; str);</ins>
</pre>
<blockquote><p>
<ins>-??- <i>Returns</i>: <code>std::getline(*this, str)</code></ins>
</p>
</blockquote>

<pre>
<ins>template&lt;class Allocator&gt;
basic_istream&lt;charT,traits&gt;&amp; getline(basic_string&lt;charT,traits,Allocator&gt;&amp; str, char_type delim);</ins>
</pre>
<blockquote><p>
<ins>-??- <i>Returns</i>: <code>std::getline(*this, str, delim)</code></ins>
</p>
</blockquote>

</blockquote>
</li>
</ol>






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