From 0ec92f1f03406aa3b3a1840045c3f38fa72665f1 Mon Sep 17 00:00:00 2001
From: Beman Dawes <bdawes@acm.org>
Date: Sat, 15 Jun 2002 21:13:12 +0000
Subject: [PATCH] Remove a couple of bugs, clarify a couple of minor points;
 from Kevlin

[SVN r14148]
---
 lexical_cast.htm | 38 ++++++++++++++++++++++++--------------
 1 file changed, 24 insertions(+), 14 deletions(-)

diff --git a/lexical_cast.htm b/lexical_cast.htm
index 47b8aaf..870068d 100644
--- a/lexical_cast.htm
+++ b/lexical_cast.htm
@@ -79,8 +79,13 @@ convenience for such conversions. For more involved conversions, such as where
 precision or formatting need tighter control than is offered by the default
 behavior of <code>lexical_cast</code>, the conventional
 <code>stringstream</code> approach is recommended. Where the conversions are
-numeric to numeric, <code><a href="cast.htm#numeric_cast">numeric_cast</a></code> may offer more reasonable
-behavior than <code>lexical_cast</code>.
+numeric to numeric, <code><a href="cast.htm#numeric_cast">numeric_cast</a></code>
+may offer more reasonable behavior than <code>lexical_cast</code>.
+<p>
+For a good discussion of the options and issues involved in string-based formatting,
+including comparison of <code>stringstream</code>, <code>lexical_cast</code>, and
+others, see Herb Sutter's article, <a href="http://www.gotw.ca/publications/mill19.htm">
+<i>The String Formatters of Manor Farm</i></a>.
 <p>
 
 <hr>
@@ -154,12 +159,8 @@ template&lt;typename Target, typename Source&gt;
 </blockquote>
 
 Returns the result of streaming <code>arg</code> into a <code>std::stringstream</code> and then
-out as a <code>Target</code> object. The conversion is parameterized by the current
-<a href="#lexical_context"><code>lexical_context</code></a>, if set. If the conversion is
-unsuccessful, a <a href="#bad_lexical_cast"><code>bad_lexical_cast</code></a> exception is thrown
-if the current <a href="#lexical_context"><code>lexical_context</code></a> is set for throwing or
-if there is no current <a href="#lexical_context"><code>lexical_context</code></a> set, otherwise a
-<code>Target()</code> is returned.
+out as a <code>Target</code> object. If the conversion is unsuccessful, a
+<a href="#bad_lexical_cast"><code>bad_lexical_cast</code></a> exception is thrown.
 <p>
 The requirements on the argument and result types are:
 <ul>
@@ -220,23 +221,32 @@ preference to the standard <code>&lt;sstream&gt;</code> header for out-of-the-bo
 
 <ul>
     <li>
-        A mechanism for providing quality-of-service control is needed, e.g. formatting and exception
-        behavior. In the name of simplicity (and release), the current version strips out an earlier
-        experimental version.
+	Improved string handling, correctly accommodating wide character strings, incompatible
+	<code>basic_string</code> types, and empty strings.
     </li>
     <li>
-        Wide character and incompatible <code>std::basic_string</code> issues need to be catered for.
+	Optimize the use of a stream away for identity conversions.
     </li>
     <li>
         An <code>interpret_cast</code> that performs a <i>do-something-reasonable</i> conversion between
         types. It would, for instance, select between <code>numeric_cast</code> and <code>lexical_cast</code>
-        based on <code>std::numeric_limits<>::is_specialized</code>.
+        based on <code>std::numeric_limits&lt;&gt;::is_specialized</code>. This would be an interesting
+	project, but there are no concrete plans to pursue this at the moment.
+    </li>
+    <li>
+        It is also worth mentioning future <i>non-directions</i>: anything that involves adding extra
+	arguments for a conversion operation is not being considered. A custom keyword cast, such as
+	<code>lexical_cast</code>, is intended to look like a built-in cast operator: built-in cast operators
+	take only a single operand. Where a higher degree of control is required over conversions, the
+	standard <code>stringstream</code> offers a more appropriate path. Where non-stream-based conversions
+	are required, <code>lexical_cast</code> is the wrong tool for the job, and so it won't be special-cased
+	for such scenarios.
     </li>
 </ul>
 
 <hr>
 
-<div align="right"><small><i>&copy; Copyright Kevlin Henney, 2000</i></small></div>
+<div align="right"><small><i>&copy; Copyright Kevlin Henney, 2000, 2002</i></small></div>
 
 </body>
 </html>