From: Bruno Haible <bruno@clisp.org>
Date: Sun, 27 Dec 2015 00:03:56 +0000 (+0100)
Subject: Add comments about the implementation of 'autosprintf::operator='.
X-Git-Tag: v0.20~503
X-Git-Url: http://git.ipfire.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=8735e2d4f1b6fc74ba05059a356f1b2f45775b16;p=thirdparty%2Fgettext.git

Add comments about the implementation of 'autosprintf::operator='.

* gettext-runtime/libasprintf/autosprintf.in.h (autosprintf::operator=): Add
comments. Rename parameter.
* gettext-runtime/libasprintf/autosprintf.cc (autosprintf::operator=): Likewise.
---

diff --git a/gettext-runtime/libasprintf/autosprintf.cc b/gettext-runtime/libasprintf/autosprintf.cc
index 0c8bff1f1..d194a309b 100644
--- a/gettext-runtime/libasprintf/autosprintf.cc
+++ b/gettext-runtime/libasprintf/autosprintf.cc
@@ -56,10 +56,12 @@ namespace gnu
     str = (src.str != NULL ? strdup (src.str) : NULL);
   }
 
-  /* Copy constructor.  Necessary because the destructor is nontrivial.  */
-  autosprintf& autosprintf::operator = (autosprintf copy)
+  /* Assignment operator.  Necessary because the destructor is nontrivial.  */
+  autosprintf& autosprintf::operator = (autosprintf temporary)
   {
-    std::swap (copy.str, this->str);
+    /* Copy-and-swap idiom.
+       See http://stackoverflow.com/questions/3279543/what-is-the-copy-and-swap-idiom  */
+    std::swap (temporary.str, this->str);
     return *this;
   }
 
diff --git a/gettext-runtime/libasprintf/autosprintf.in.h b/gettext-runtime/libasprintf/autosprintf.in.h
index 1c9eb18a1..9c34bc92b 100644
--- a/gettext-runtime/libasprintf/autosprintf.in.h
+++ b/gettext-runtime/libasprintf/autosprintf.in.h
@@ -47,7 +47,8 @@ namespace gnu
                 _AUTOSPRINTF_ATTRIBUTE_FORMAT();
     /* Copy constructor.  */
     autosprintf (const autosprintf& src);
-    autosprintf& operator = (autosprintf copy);
+    /* Assignment operator.  */
+    autosprintf& operator = (autosprintf temporary);
     /* Destructor: frees the temporarily allocated string.  */
     ~autosprintf ();
     /* Conversion to string.  */