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<title>Issue 667: money_get's widened minus sign</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="667"><a href="lwg-closed.html#667">667</a>. <code>money_get</code>'s widened minus sign</h3>
<p><b>Section:</b> 28.3.4.7.2.3 <a href="https://wg21.link/locale.money.get.virtuals">[locale.money.get.virtuals]</a> <b>Status:</b> <a href="lwg-active.html#NAD">NAD</a>
 <b>Submitter:</b> Thomas Plum <b>Opened:</b> 2007-04-16 <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#locale.money.get.virtuals">issues</a> in [locale.money.get.virtuals].</p>
<p><b>View all issues with</b> <a href="lwg-status.html#NAD">NAD</a> status.</p>
<p><b>Discussion:</b></p>
<p>
28.3.4.7.2.3 <a href="https://wg21.link/locale.money.get.virtuals">[locale.money.get.virtuals]</a>, para 1 says:
</p>

<blockquote><p>
The result is returned as an integral value
stored in <code>units</code> or as a sequence of digits possibly preceded by a
minus sign (as produced by <code>ct.widen(c)</code> where <code>c</code> is '-' or in the range
from '0' through '9', inclusive) stored in <code>digits</code>.
</p></blockquote>

<p>
The following
objection has been raised:
</p>

<blockquote><p>
Some implementations interpret this to mean that a facet derived from
<code>ctype&lt;wchar_t&gt;</code> can provide its own member <code>do_widen(char)</code>
which produces e.g. <code>L'@'</code> for the "widened" minus sign, and that the
<code>'@'</code> symbol will appear in the resulting sequence of digits.  Other
implementations have assumed that one or more places in the standard permit the
implementation to "hard-wire" <code>L'-'</code> as the "widened" minus sign.  Are
both interpretations permissible, or only  one?
</p></blockquote>

<p>
[Plum ref _222612Y14]
</p>

<p>
Furthermore: if <code>ct.widen('9')</code> produces <code>L'X'</code> (a non-digit), does a
parse fail if a <code>'9'</code> appears in the subject string? [Plum ref _22263Y33]
</p>

<p><i>[
Kona (2007): Bill and Dietmar to provide proposed wording.
]</i></p>


<p><i>[
post Bellevue: Bill adds:
]</i></p>


<blockquote><p>
The Standard is clear that the minus sign stored in <code>digits</code> is <code>ct.widen('-')</code>.
The subject string must contain characters <code>c</code> in the set <code>[-0123456789]</code>
which are translated by <code>ct.widen(c)</code> calls before being stored in <code>digits</code>;
the widened characters are not relevant to the parsing of the subject string.
</p></blockquote>

<p><i>[
Batavia (2009-05):
]</i></p>

<blockquote><p>
We agree with Bill's comment above,
in line with the first of the interpretations offered in the issue.
Move to NAD.
</p></blockquote>


<p id="res-667"><b>Proposed resolution:</b></p>
<p>
</p>





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