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diff --git a/libstdc++-v3/docs/html/24_iterators/howto.html b/libstdc++-v3/docs/html/24_iterators/howto.html index 90c53df18ac..c22df9acf42 100644 --- a/libstdc++-v3/docs/html/24_iterators/howto.html +++ b/libstdc++-v3/docs/html/24_iterators/howto.html @@ -1,13 +1,17 @@ -<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.0//EN"> -<html> +<?xml version="1.0" encoding="ISO-8859-1"?> +<!DOCTYPE html + PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" + "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd"> + +<html xmlns="http://www.w3.org/1999/xhtml" xml:lang="en" lang="en"> <head> - <meta http-equiv="Content-Type" content="text/html; charset=iso-8859-1"> - <meta name="AUTHOR" content="pme@gcc.gnu.org (Phil Edwards)"> - <meta name="KEYWORDS" content="HOWTO, libstdc++, GCC, g++, libg++, STL"> - <meta name="DESCRIPTION" content="HOWTO for the libstdc++ chapter 24."> - <meta name="GENERATOR" content="vi and eight fingers"> + <meta http-equiv="Content-Type" content="text/html; charset=iso-8859-1" /> + <meta name="AUTHOR" content="pme@gcc.gnu.org (Phil Edwards)" /> + <meta name="KEYWORDS" content="HOWTO, libstdc++, GCC, g++, libg++, STL" /> + <meta name="DESCRIPTION" content="HOWTO for the libstdc++ chapter 24." /> + <meta name="GENERATOR" content="vi and eight fingers" /> <title>libstdc++-v3 HOWTO: Chapter 24</title> -<link rel="StyleSheet" href="../lib3styles.css"> +<link rel="StyleSheet" href="../lib3styles.css" /> </head> <body> @@ -19,14 +23,14 @@ <!-- ####################################################### --> -<hr> +<hr /> <h1>Contents</h1> <ul> - <li><a href="#1">They ain't pointers!</a> - <li><a href="#2">It ends <em>where?</em></a> + <li><a href="#1">They ain't pointers!</a></li> + <li><a href="#2">It ends <em>where?</em></a></li> </ul> -<hr> +<hr /> <!-- ####################################################### --> @@ -67,41 +71,46 @@ <a href="../faq/index.html">to the FAQ</a>. </p> -<hr> +<hr /> <h2><a name="2">It ends <em>where?</em></a></h2> <p>This starts off sounding complicated, but is actually very easy, especially towards the end. Trust me. - </p> + </p> <p>Beginners usually have a little trouble understand the whole 'past-the-end' thing, until they remember their early algebra classes - (see, they </em>told</em> you that stuff would come in handy!) and + (see, they <em>told</em> you that stuff would come in handy!) and the concept of half-open ranges. </p> <p>First, some history, and a reminder of some of the funkier rules in C and C++ for builtin arrays. The following rules have always been true for both languages: - <ol> - <li>You can point anywhere in the array, <em>or to the first element - past the end of the array</em>. A pointer that points to one - past the end of the array is guaranteed to be as unique as a - pointer to somewhere inside the array, so that you can compare - such pointers safely. - <li>You can only dereference a pointer that points into an array. - If your array pointer points outside the array -- even to just - one past the end -- and you dereference it, Bad Things happen. - <li>Strictly speaking, simply pointing anywhere else invokes - undefined behavior. Most programs won't puke until such a - pointer is actually dereferenced, but the standards leave that - up to the platform. - </ol> - The reason this past-the-end addressing was allowed is to make it + </p> + <ol> + <li>You can point anywhere in the array, <em>or to the first element + past the end of the array</em>. A pointer that points to one + past the end of the array is guaranteed to be as unique as a + pointer to somewhere inside the array, so that you can compare + such pointers safely. + </li> + <li>You can only dereference a pointer that points into an array. + If your array pointer points outside the array -- even to just + one past the end -- and you dereference it, Bad Things happen. + </li> + <li>Strictly speaking, simply pointing anywhere else invokes + undefined behavior. Most programs won't puke until such a + pointer is actually dereferenced, but the standards leave that + up to the platform. + </li> + </ol> + <p>The reason this past-the-end addressing was allowed is to make it easy to write a loop to go over an entire array, e.g., while (*d++ = *s++);. </p> <p>So, when you think of two pointers delimiting an array, don't think of them as indexing 0 through n-1. Think of them as <em>boundary markers</em>: - <pre> + </p> + <pre> beginning end | | @@ -121,8 +130,8 @@ | | dereference 'end'. beginning end - </pre> - See? Everything between the boundary markers is part of the array. + </pre> + <p>See? Everything between the boundary markers is part of the array. Simple. </p> <p>Now think back to your junior-high school algebra course, when you @@ -171,7 +180,7 @@ <!-- ####################################################### --> -<hr> +<hr /> <p class="fineprint"><em> See <a href="../17_intro/license.html">license.html</a> for copying conditions. Comments and suggestions are welcome, and may be sent to |