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diff --git a/libstdc++-v3/docs/html/ext/howto.html b/libstdc++-v3/docs/html/ext/howto.html deleted file mode 100644 index fff3410180f..00000000000 --- a/libstdc++-v3/docs/html/ext/howto.html +++ /dev/null @@ -1,652 +0,0 @@ -<?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="Notes for the libstdc++ extensions." /> - <meta name="GENERATOR" content="vi and eight fingers" /> - <title>libstdc++-v3 HOWTO: Extensions</title> -<link rel="StyleSheet" href="../lib3styles.css" type="text/css" /> -<link rel="Start" href="../documentation.html" type="text/html" - title="GNU C++ Standard Library" /> -<link rel="Prev" href="../27_io/howto.html" type="text/html" - title="Input/Output" /> -<link rel="Bookmark" href="sgiexts.html" type="text/html" - title="SGI extensions" /> -<link rel="Bookmark" href="mt_allocator.html" type="text/html" - title="__mt_alloc" /> -<link rel="Copyright" href="../17_intro/license.html" type="text/html" /> -</head> -<body> - -<h1 class="centered"><a name="top">Extensions</a></h1> - -<p>Here we will make an attempt at describing the non-Standard extensions to - the library. Some of these are from SGI's STL, some of these are GNU's, - and some just seemed to appear on the doorstep. -</p> -<p><strong>Before you leap in and use these</strong>, be aware of two things: -</p> -<ol> - <li>Non-Standard means exactly that. The behavior, and the very - existence, of these extensions may change with little or no - warning. (Ideally, the really good ones will appear in the next - revision of C++.) Also, other platforms, other compilers, other - versions of g++ or libstdc++-v3 may not recognize these names, or - treat them differently, or... </li> - <li>You should know how to <a href="../faq/index.html#5_4">access - these headers properly</a>. </li> -</ol> - - -<!-- ####################################################### --> -<hr /> -<h1>Contents</h1> -<ul> - <li><a href="#1">Ropes and trees and hashes, oh my!</a></li> - <li><a href="#2">Added members and types</a></li> - <li><a href="mt_allocator.html"><code>__mt_alloc</code> </a></li> - <li><a href="#4">Compile-time checks</a></li> - <li><a href="#5">LWG Issues</a></li> - <li><a href="../18_support/howto.html#6">Demangling</a></li> -</ul> - -<hr /> - -<!-- ####################################################### --> - -<h2><a name="1">Ropes and trees and hashes, oh my!</a></h2> - <p>The SGI headers</p> - <pre> - <bvector> - <hash_map> - <hash_set> - <rope> - <slist> - <tree> - </pre> - <p>are all here; <code><bvector></code> exposes the old bit_vector - class that was used before specialization of vector<bool> was - available (it's actually a typedef for the specialization now). - <code><hash_map></code> and <code><hash_set></code> - are discussed further below. <code><rope></code> is the SGI - specialization for large strings ("rope," "large - strings," get it? love those SGI folks). - <code><slist></code> is a singly-linked list, for when the - doubly-linked <code>list<></code> is too much space overhead, and - <code><tree></code> exposes the red-black tree classes used in the - implementation of the standard maps and sets. - </p> - <p>Okay, about those hashing classes... I'm going to foist most of the - work off onto SGI's own site. - </p> - <p>Each of the associative containers map, multimap, set, and multiset - have a counterpart which uses a - <a href="http://www.sgi.com/tech/stl/HashFunction.html">hashing - function</a> to do the arranging, instead of a strict weak ordering - function. The classes take as one of their template parameters a - function object that will return the hash value; by default, an - instantiation of - <a href="http://www.sgi.com/tech/stl/hash.html">hash</a>. - You should specialize this functor for your class, or define your own, - before trying to use one of the hashing classes. - </p> - <p>The hashing classes support all the usual associative container - functions, as well as some extra constructors specifying the number - of buckets, etc. - </p> - <p>Why would you want to use a hashing class instead of the - "normal" implementations? Matt Austern writes: - </p> - <blockquote><em>[W]ith a well chosen hash function, hash tables - generally provide much better average-case performance than binary - search trees, and much worse worst-case performance. So if your - implementation has hash_map, if you don't mind using nonstandard - components, and if you aren't scared about the possibility of - pathological cases, you'll probably get better performance from - hash_map.</em></blockquote> - <p>(Side note: for those of you wondering, <strong>"Why wasn't a hash - table included in the Standard in the first #!$@ place?"</strong> - I'll give a quick answer: it was proposed, but too late and in too - unorganized a fashion. Some sort of hashing will undoubtedly be - included in a future Standard.) - </p> - <p>Return <a href="#top">to top of page</a> or - <a href="../faq/index.html">to the FAQ</a>. - </p> - -<hr /> -<h2><a name="2">Added members and types</a></h2> - <p>Some of the classes in the Standard Library have additional - publicly-available members, and some classes are themselves not in - the standard. Of those, some are intended purely for the implementors, - for example, additional typedefs. Those won't be described here - (or anywhere else). - </p> - <ul> - <li>The extensions added by SGI are so numerous that they have - <a href="sgiexts.html">their own page</a>. Since the SGI STL is no - longer actively maintained, we will try and keep this code working - ourselves.</li> - <li>Extensions allowing <code>filebuf</code>s to be constructed from - stdio types are described in the - <a href="../27_io/howto.html#11">chapter 27 notes</a>.</li> - </ul> - <p>Return <a href="#top">to top of page</a> or - <a href="../faq/index.html">to the FAQ</a>. - </p> - -<hr /> -<h2><a name="4">Compile-time checks</a></h2> - <p>Currently libstdc++-v3 uses the concept checkers from the Boost - library to perform <a href="../19_diagnostics/howto.html#3">optional - compile-time checking</a> of template instantiations of the standard - containers. They are described in the linked-to page. - </p> - <p>Return <a href="#top">to top of page</a> or - <a href="../faq/index.html">to the FAQ</a>. - </p> - -<hr /> -<h2><a name="5">LWG Issues</a></h2> - <p>Everybody's got issues. Even the C++ Standard Library. - </p> - <p>The Library Working Group, or LWG, is the ISO subcommittee responsible - for making changes to the library. They periodically publish an - Issues List containing problems and possible solutions. As they reach - a consensus on proposed solutions, we often incorporate the solution - into libstdc++-v3. - </p> - <p>Here are the issues which have resulted in code changes to the library. - The links are to the specific defect reports from a <strong>partial - copy</strong> of the Issues List. You can read the full version online - at the <a href="http://www.open-std.org/jtc1/sc22/wg21/">ISO C++ - Committee homepage</a>, linked to on the - <a href="http://gcc.gnu.org/readings.html">GCC "Readings" - page</a>. If - you spend a lot of time reading the issues, we recommend downloading - the ZIP file and reading them locally. - </p> - <p>(NB: <strong>partial copy</strong> means that not all links within - the lwg-*.html pages will work. - Specifically, links to defect reports that have not been accorded full - DR status will probably break. Rather than trying to mirror the - entire issues list on our overworked web server, we recommend you go - to the LWG homepage instead.) - </p> - <p> - If a DR is not listed here, we may simply not have gotten to it yet; - feel free to submit a patch. Search the include/bits and src - directories for appearances of _GLIBCXX_RESOLVE_LIB_DEFECTS for - examples of style. Note that we usually do not make changes to the code - until an issue has reached <a href="lwg-active.html#DR">DR</a> status. - </p> - <dl> - <dt><a href="lwg-defects.html#5">5</a>: - <em>string::compare specification questionable</em> - </dt> - <dd>This should be two overloaded functions rather than a single function. - </dd> - - <dt><a href="lwg-defects.html#17">17</a>: - <em>Bad bool parsing</em> - </dt> - <dd>Apparently extracting Boolean values was messed up... - </dd> - - <dt><a href="lwg-defects.html#19">19</a>: - <em>"Noconv" definition too vague</em> - </dt> - <dd>If <code>codecvt::do_in</code> returns <code>noconv</code> there are - no changes to the values in <code>[to, to_limit)</code>. - </dd> - - <dt><a href="lwg-defects.html#22">22</a>: - <em>Member open vs flags</em> - </dt> - <dd>Re-opening a file stream does <em>not</em> clear the state flags. - </dd> - - <dt><a href="lwg-defects.html#25">25</a>: - <em>String operator<< uses width() value wrong</em> - </dt> - <dd>Padding issues. - </dd> - - <dt><a href="lwg-defects.html#48">48</a>: - <em>Use of non-existent exception constructor</em> - </dt> - <dd>An instance of <code>ios_base::failure</code> is constructed instead. - </dd> - - <dt><a href="lwg-defects.html#49">49</a>: - <em>Underspecification of ios_base::sync_with_stdio</em> - </dt> - <dd>The return type is the <em>previous</em> state of synchronization. - </dd> - - <dt><a href="lwg-defects.html#50">50</a>: - <em>Copy constructor and assignment operator of ios_base</em> - </dt> - <dd>These members functions are declared <code>private</code> and are - thus inaccessible. Specifying the correct semantics of - "copying stream state" was deemed too complicated. - </dd> - - <dt><a href="lwg-defects.html#60">60</a>: - <em>What is a formatted input function?</em> - </dt> - <dd>This DR made many widespread changes to <code>basic_istream</code> - and <code>basic_ostream</code> all of which have been implemented. - </dd> - - <dt><a href="lwg-defects.html#63">63</a>: - <em>Exception-handling policy for unformatted output</em> - </dt> - <dd>Make the policy consistent with that of formatted input, unformatted - input, and formatted output. - </dd> - - <dt><a href="lwg-defects.html#68">68</a>: - <em>Extractors for char* should store null at end</em> - </dt> - <dd>And they do now. An editing glitch in the last item in the list of - [27.6.1.2.3]/7. - </dd> - - <dt><a href="lwg-defects.html#74">74</a>: - <em>Garbled text for codecvt::do_max_length</em> - </dt> - <dd>The text of the standard was gibberish. Typos gone rampant. - </dd> - - <dt><a href="lwg-defects.html#75">75</a>: - <em>Contradiction in codecvt::length's argument types</em> - </dt> - <dd>Change the first parameter to <code>stateT&</code> and implement - the new effects paragraph. - </dd> - - <dt><a href="lwg-defects.html#83">83</a>: - <em>string::npos vs. string::max_size()</em> - </dt> - <dd>Safety checks on the size of the string should test against - <code>max_size()</code> rather than <code>npos</code>. - </dd> - - <dt><a href="lwg-defects.html#90">90</a>: - <em>Incorrect description of operator>> for strings</em> - </dt> - <dd>The effect contain <code>isspace(c,getloc())</code> which must be - replaced by <code>isspace(c,is.getloc())</code>. - </dd> - - <dt><a href="lwg-defects.html#91">91</a>: - <em>Description of operator>> and getline() for string<> - might cause endless loop</em> - </dt> - <dd>They behave as a formatted input function and as an unformatted - input function, respectively (except that <code>getline</code> is - not required to set <code>gcount</code>). - </dd> - - <dt><a href="lwg-defects.html#103">103</a>: - <em>set::iterator is required to be modifiable, but this allows - modification of keys.</em> - </dt> - <dd>For associative containers where the value type is the same as - the key type, both <code>iterator</code> and <code>const_iterator - </code> are constant iterators. - </dd> - - <dt><a href="lwg-defects.html#109">109</a>: - <em>Missing binders for non-const sequence elements</em> - </dt> - <dd>The <code>binder1st</code> and <code>binder2nd</code> didn't have an - <code>operator()</code> taking a non-const parameter. - </dd> - - <dt><a href="lwg-defects.html#110">110</a>: - <em>istreambuf_iterator::equal not const</em> - </dt> - <dd>This was not a const member function. Note that the DR says to - replace the function with a const one; we have instead provided an - overloaded version with identical contents. - </dd> - - <dt><a href="lwg-defects.html#117">117</a>: - <em>basic_ostream uses nonexistent num_put member functions</em> - </dt> - <dd><code>num_put::put()</code> was overloaded on the wrong types. - </dd> - - <dt><a href="lwg-defects.html#118">118</a>: - <em>basic_istream uses nonexistent num_get member functions</em> - </dt> - <dd>Same as 117, but for <code>num_get::get()</code>. - </dd> - - <dt><a href="lwg-defects.html#129">129</a>: - <em>Need error indication from seekp() and seekg()</em> - </dt> - <dd>These functions set <code>failbit</code> on error now. - </dd> - - <dt><a href="lwg-defects.html#136">136</a>: - <em>seekp, seekg setting wrong streams?</em> - </dt> - <dd><code>seekp</code> should only set the output stream, and - <code>seekg</code> should only set the input stream. - </dd> - -<!--<dt><a href="lwg-defects.html#159">159</a>: - <em>Strange use of underflow()</em> - </dt> - <dd>In fstream.tcc, the basic_filebuf<>::showmanyc() function - should probably not be calling <code>underflow()</code>. - </dd> --> - - <dt><a href="lwg-defects.html#167">167</a>: - <em>Improper use of traits_type::length()</em> - </dt> - <dd><code>op<<</code> with a <code>const char*</code> was - calculating an incorrect number of characters to write. - </dd> - - <dt><a href="lwg-defects.html#169">169</a>: - <em>Bad efficiency of overflow() mandated</em> - </dt> - <dd>Grow efficiently the internal array object. - </dd> - - <dt><a href="lwg-defects.html#171">171</a>: - <em>Strange seekpos() semantics due to joint position</em> - </dt> - <dd>Quite complex to summarize... - </dd> - - <dt><a href="lwg-defects.html#181">181</a>: - <em>make_pair() unintended behavior</em> - </dt> - <dd>This function used to take its arguments as reference-to-const, now - it copies them (pass by value). - </dd> - - <dt><a href="lwg-defects.html#195">195</a>: - <em>Should basic_istream::sentry's constructor ever set eofbit?</em> - </dt> - <dd>Yes, it can, specifically if EOF is reached while skipping whitespace. - </dd> - - <dt><a href="lwg-defects.html#211">211</a>: - <em>operator>>(istream&, string&) doesn't set failbit</em> - </dt> - <dd>If nothing is extracted into the string, <code>op>></code> now - sets <code>failbit</code> (which can cause an exception, etc., etc.). - </dd> - - <dt><a href="lwg-defects.html#214">214</a>: - <em>set::find() missing const overload</em> - </dt> - <dd>Both <code>set</code> and <code>multiset</code> were missing - overloaded find, lower_bound, upper_bound, and equal_range functions - for const instances. - </dd> - - <dt><a href="lwg-defects.html#231">231</a>: - <em>Precision in iostream?</em> - </dt> - <dd>For conversion from a floating-point type, <code>str.precision()</code> - is specified in the conversion specification. - </dd> - - <dt><a href="lwg-active.html#233">233</a>: - <em>Insertion hints in associative containers</em> - </dt> - <dd>Implement N1780, first check before then check after, insert as close - to hint as possible. - </dd> - - <dt><a href="lwg-defects.html#235">235</a>: - <em>No specification of default ctor for reverse_iterator</em> - </dt> - <dd>The declaration of <code>reverse_iterator</code> lists a default constructor. - However, no specification is given what this constructor should do. - </dd> - - <dt><a href="lwg-defects.html#241">241</a>: - <em>Does unique_copy() require CopyConstructible and Assignable?</em> - </dt> - <dd>Add an helper for forward_iterator/output_iterator, fix the existing - one for input_iterator/output_iterator not to rely on Assignability. - </dd> - - <dt><a href="lwg-defects.html#243">243</a>: - <em>get and getline when sentry reports failure</em> - </dt> - <dd>Store a null character only if the character array has a non-zero size. - </dd> - - <dt><a href="lwg-defects.html#251">251</a>: - <em>basic_stringbuf missing allocator_type</em> - </dt> - <dd>This nested typedef was originally not specified. - </dd> - - <dt><a href="lwg-defects.html#253">253</a>: - <em>valarray helper functions are almost entirely useless</em> - </dt> - <dd>Make the copy constructor and copy-assignment operator declarations - public in gslice_array, indirect_array, mask_array, slice_array; provide - definitions. - </dd> - - <dt><a href="lwg-defects.html#265">265</a>: - <em>std::pair::pair() effects overly restrictive</em> - </dt> - <dd>The default ctor would build its members from copies of temporaries; - now it simply uses their respective default ctors. - </dd> - - <dt><a href="lwg-defects.html#266">266</a>: - <em>bad_exception::~bad_exception() missing Effects clause</em> - </dt> - <dd>The <code>bad_</code>* classes no longer have destructors (they - are trivial), since no description of them was ever given. - </dd> - - <dt><a href="lwg-defects.html#271">271</a>: - <em>basic_iostream missing typedefs</em> - </dt> - <dd>The typedefs it inherits from its base classes can't be used, since - (for example) <code>basic_iostream<T>::traits_type</code> is ambiguous. - </dd> - - <dt><a href="lwg-defects.html#275">275</a>: - <em>Wrong type in num_get::get() overloads</em> - </dt> - <dd>Similar to 118. - </dd> - - <dt><a href="lwg-defects.html#280">280</a>: - <em>Comparison of reverse_iterator to const reverse_iterator</em> - </dt> - <dd>Add global functions with two template parameters. - (NB: not added for now a templated assignment operator) - </dd> - - <dt><a href="lwg-defects.html#292">292</a>: - <em>Effects of a.copyfmt (a)</em> - </dt> - <dd>If <code>(this == &rhs)</code> do nothing. - </dd> - - <dt><a href="lwg-defects.html#300">300</a>: - <em>List::merge() specification incomplete</em> - </dt> - <dd>If <code>(this == &x)</code> do nothing. - </dd> - - <dt><a href="lwg-defects.html#303">303</a>: - <em>Bitset input operator underspecified</em> - </dt> - <dd>Basically, compare the input character to <code>is.widen(0)</code> - and <code>is.widen(1)</code>. - </dd> - - <dt><a href="lwg-defects.html#305">305</a>: - <em>Default behavior of codecvt<wchar_t, char, mbstate_t>::length()</em> - </dt> - <dd>Do not specify what <code>codecvt<wchar_t, char, mbstate_t>::do_length</code> - must return. - </dd> - - <dt><a href="lwg-defects.html#328">328</a>: - <em>Bad sprintf format modifier in money_put<>::do_put()</em> - </dt> - <dd>Change the format string to "%.0Lf". - </dd> - - <dt><a href="lwg-defects.html#365">365</a>: - <em>Lack of const-qualification in clause 27</em> - </dt> - <dd>Add const overloads of <code>is_open</code>. - </dd> - - <dt><a href="lwg-defects.html#389">389</a>: - <em>Const overload of valarray::operator[] returns by value</em> - </dt> - <dd>Change it to return a <code>const T&</code>. - </dd> - - <dt><a href="lwg-defects.html#402">402</a>: - <em>Wrong new expression in [some_]allocator::construct</em> - </dt> - <dd>Replace "new" with "::new". - </dd> - - <dt><a href="lwg-defects.html#409">409</a>: - <em>Closing an fstream should clear the error state</em> - </dt> - <dd>Have <code>open</code> clear the error flags. - </dd> - - <dt><a href="lwg-active.html#431">431</a>: - <em>Swapping containers with unequal allocators</em> - </dt> - <dd>Implement Option 3, as per N1599. - </dd> - - <dt><a href="lwg-defects.html#432">432</a>: - <em>stringbuf::overflow() makes only one write position - available</em> - </dt> - <dd>Implement the resolution, beyond DR 169. - </dd> - - <dt><a href="lwg-defects.html#434">434</a>: - <em>bitset::to_string() hard to use</em> - </dt> - <dd>Add three overloads, taking fewer template arguments. - </dd> - - <dt><a href="lwg-defects.html#438">438</a>: - <em>Ambiguity in the "do the right thing" clause</em> - </dt> - <dd>Implement the resolution, basically cast less. - </dd> - - <dt><a href="lwg-defects.html#453">453</a>: - <em>basic_stringbuf::seekoff need not always fail for an empty stream</em> - </dt> - <dd>Don't fail if the next pointer is null and newoff is zero. - </dd> - - <dt><a href="lwg-defects.html#455">455</a>: - <em>cerr::tie() and wcerr::tie() are overspecified</em> - </dt> - <dd>Initialize cerr tied to cout and wcerr tied to wcout. - </dd> - - <dt><a href="lwg-defects.html#464">464</a>: - <em>Suggestion for new member functions in standard containers</em> - </dt> - <dd>Add <code>data()</code> to <code>std::vector</code> and - <code>at(const key_type&)</code> to <code>std::map</code>. - </dd> - - <dt><a href="lwg-defects.html#508">508</a>: - <em>Bad parameters for ranlux64_base_01</em> - </dt> - <dd>Fix the parameters. - </dd> - - <dt><a href="lwg-closed.html#512">512</a>: - <em>Seeding subtract_with_carry_01 from a single unsigned long</em> - </dt> - <dd>Construct a <code>linear_congruential</code> engine and seed with it. - </dd> - - <dt><a href="lwg-active.html#526">526</a>: - <em>Is it undefined if a function in the standard changes in - parameters?</em> - </dt> - <dd>Use &value. - </dd> - - <dt><a href="lwg-defects.html#538">538</a>: - <em>241 again: Does unique_copy() require CopyConstructible - and Assignable?</em> - </dt> - <dd>In case of input_iterator/output_iterator rely on Assignability of - input_iterator' value_type. - </dd> - - <dt><a href="lwg-defects.html#541">541</a>: - <em>shared_ptr template assignment and void</em> - </dt> - <dd>Add an auto_ptr<void> specialization. - </dd> - - <dt><a href="lwg-active.html#543">543</a>: - <em>valarray slice default constructor</em> - </dt> - <dd>Follow the straightforward proposed resolution. - </dd> - - <dt><a href="lwg-active.html#586">586</a>: - <em>string inserter not a formatted function</em> - </dt> - <dd>Change it to be a formatted output function (i.e. catch exceptions). - </dd> -<!-- - <dt><a href="lwg-defects.html#"></a>: - <em></em> - </dt> - <dd> - </dd> - ---> - </dl> - <p>Return <a href="#top">to top of page</a> or - <a href="../faq/index.html">to the FAQ</a>. - </p> - - -<!-- ####################################################### --> - -<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 -<a href="mailto:libstdc++@gcc.gnu.org">the libstdc++ mailing list</a>. -</em></p> - - -</body> -</html> |