STL extensions from SGI(3)

NAME
STL extensions from SGI -

Detailed Description

Because libstdc++-v3 based its implementation of the STL subsections of the library on the SGI 3.3 implementation, we inherited their extensions as well.

They are additionally documented in the online documentation, a copy of which is also shipped with the library source code (in .../docs/html/documentation.html). You can also read the documentation on SGI's site, which is still running even though the code is not maintained.

NB that the following notes are pulled from various comments all over the place, so they may seem stilted.

The identity_element functions are not part of the C++ standard; SGI provided them as an extension. Its argument is an operation, and its return value is the identity element for that operation. It is overloaded for addition and multiplication, and you can overload it for your own nefarious operations.

As an extension to the binders, SGI provided composition functors and wrapper functions to aid in their creation. The unary_compose functor is constructed from two functions/functors, f and g. Calling operator() with a single argument x returns f(g(x)). The function compose1 takes the two functions and constructs a unary_compose variable for you.

binary_compose is constructed from three functors, f, g1, and g2. Its operator() returns f(g1(x),g2(x)). The function takes f, g1, and g2, and constructs the binary_compose instance for you. For example, if f returns an int, then

  int answer = (compose2(f,g1,g2))(x);

 is equivalent to

  int temp1 = g1(x);
  int temp2 = g2(x);
  int answer = f(temp1,temp2);

 But the first form is more compact, and can be passed around as a functor to other algorithms.

As an extension, SGI provided a functor called identity. When a functor is required but no operations are desired, this can be used as a pass-through. Its operator() returns its argument unchanged.

select1st and select2nd are extensions provided by SGI. Their operator()s take a std::pair as an argument, and return either the first member or the second member, respectively. They can be used (especially with the composition functors) to 'strip' data from a sequence before performing the remainder of an algorithm.

The operator() of the project1st functor takes two arbitrary arguments and returns the first one, while project2nd returns the second one. They are extensions provided by SGI.

These three functors are each constructed from a single arbitrary variable/value. Later, their operator()s completely ignore any arguments passed, and return the stored value.

•   constant_void_fun's operator() takes no arguments

•   constant_unary_fun's operator() takes one argument (ignored)

•   constant_binary_fun's operator() takes two arguments (ignored)

The helper creator functions constant0, constant1, and constant2 each take a 'result' argument and construct variables of the appropriate functor type.

  Classes
class binary_compose
An SGI extension .
struct constant_binary_fun
An SGI extension .
struct constant_unary_fun
An SGI extension .
struct constant_void_fun
An SGI extension .
class hash_map
class hash_multimap
class hash_multiset
class hash_set
struct project1st
An SGI extension .
struct project2nd
An SGI extension .
class rope
struct select1st
An SGI extension .
struct select2nd
An SGI extension .
class slist
class subtractive_rng
struct temporary_buffer
class unary_compose
An SGI extension .
bitset< _Nb > & std::bitset::_Unchecked_set (size_t __pos)

  Functions
template<typename _Tp, typename _Compare> const _Tp & std::__median (const _Tp &__a, const _Tp &__b, const _Tp &__c, _Compare __comp)
template<typename _Tp> const _Tp & std::__median (const _Tp &__a, const _Tp &__b, const _Tp &__c)
size_t std::bitset::_Find_first () const
size_t std::bitset::_Find_next (size_t __prev) const
template<class _Operation1, class _Operation2> unary_compose< _Operation1, _Operation2 > __gnu_cxx::compose1 (const _Operation1 &__fn1, const _Operation2 &__fn2)
template<class _Operation1, class _Operation2, class _Operation3> binary_compose< _Operation1, _Operation2, _Operation3 > __gnu_cxx::compose2 (const _Operation1 &__fn1, const _Operation2 &__fn2, const _Operation3 &__fn3)
template<class _Result> constant_void_fun< _Result > __gnu_cxx::constant0 (const _Result &__val)
template<class _Result> constant_unary_fun< _Result, _Result > __gnu_cxx::constant1 (const _Result &__val)
template<class _Result> constant_binary_fun< _Result, _Result, _Result > __gnu_cxx::constant2 (const _Result &__val)
template<typename _InputIterator, typename _Size, typename _OutputIterator> pair< _InputIterator, _OutputIterator > __gnu_cxx::copy_n (_InputIterator __first, _Size __count, _OutputIterator __result)
template<class _Tp> _Tp __gnu_cxx::identity_element (std::multiplies< _Tp >)
template<class _Tp> _Tp __gnu_cxx::identity_element (std::plus< _Tp >)
template<typename _ForwardIter, typename _Tp> void __gnu_cxx::iota (_ForwardIter __first, _ForwardIter __last, _Tp __value)
template<typename _RandomAccessIterator, typename _StrictWeakOrdering> bool __gnu_cxx::is_heap (_RandomAccessIterator __first, _RandomAccessIterator __last, _StrictWeakOrdering __comp)
template<typename _RandomAccessIterator> bool __gnu_cxx::is_heap (_RandomAccessIterator __first, _RandomAccessIterator __last)
template<typename _ForwardIterator, typename _StrictWeakOrdering> bool __gnu_cxx::is_sorted (_ForwardIterator __first, _ForwardIterator __last, _StrictWeakOrdering __comp)
template<typename _ForwardIterator> bool __gnu_cxx::is_sorted (_ForwardIterator __first, _ForwardIterator __last)
template<typename _InputIterator1, typename _InputIterator2> int __gnu_cxx::lexicographical_compare_3way (_InputIterator1 __first1, _InputIterator1 __last1, _InputIterator2 __first2, _InputIterator2 __last2)
template<typename _Tp, typename _Integer> _Tp __gnu_cxx::power (_Tp __x, _Integer __n)
template<typename _Tp, typename _Integer, typename _MonoidOperation> _Tp __gnu_cxx::power (_Tp __x, _Integer __n, _MonoidOperation __monoid_op)
template<typename _InputIterator, typename _RandomAccessIterator, typename _RandomNumberGenerator> _RandomAccessIterator __gnu_cxx::random_sample (_InputIterator __first, _InputIterator __last, _RandomAccessIterator __out_first, _RandomAccessIterator __out_last, _RandomNumberGenerator &__rand)
template<typename _InputIterator, typename _RandomAccessIterator> _RandomAccessIterator __gnu_cxx::random_sample (_InputIterator __first, _InputIterator __last, _RandomAccessIterator __out_first, _RandomAccessIterator __out_last)
template<typename _ForwardIterator, typename _OutputIterator, typename _Distance, typename _RandomNumberGenerator> _OutputIterator __gnu_cxx::random_sample_n (_ForwardIterator __first, _ForwardIterator __last, _OutputIterator __out, const _Distance __n, _RandomNumberGenerator &__rand)
template<typename _ForwardIterator, typename _OutputIterator, typename _Distance> _OutputIterator __gnu_cxx::random_sample_n (_ForwardIterator __first, _ForwardIterator __last, _OutputIterator __out, const _Distance __n)
template<typename _InputIter, typename _Size, typename _ForwardIter> pair< _InputIter, _ForwardIter > __gnu_cxx::uninitialized_copy_n (_InputIter __first, _Size __count, _ForwardIter __result)

Function Documentation

  const _Tp& std::__median (const _Tp & __a, const _Tp & __b, const _Tp & __c, _Compare __comp) [inline]

Find the median of three values using a predicate for comparison.

Parameters:
    a A value.
    b A value.
    c A value.
    comp A binary predicate.

Returns:
    One of a, b or c.

If {l,m,n} is some convolution of {a,b,c} such that comp(l,m) and comp(m,n) are both true then the value returned will be m. This is an SGI extension.

Definition at line 121 of file stl_algo.h.

References __glibcxx_function_requires.

  const _Tp& std::__median (const _Tp & __a, const _Tp & __b, const _Tp & __c) [inline]

Find the median of three values.

Parameters:
    a A value.
    b A value.
    c A value.

Returns:
    One of a, b or c.

If {l,m,n} is some convolution of {a,b,c} such that l<=m<=n then the value returned will be m. This is an SGI extension.

Definition at line 87 of file stl_algo.h.

References __glibcxx_function_requires.

Referenced by std::__introsort_loop(), and std::nth_element().

  size_t _Find_first () const [inline, inherited]

Finds the index of the first 'on' bit.

Returns:
    The index of the first bit set, or size() if not found.

See also:
    _Find_next

Definition at line 1129 of file bitset.

References _Base_bitset< _GLIBCXX_BITSET_WORDS(_Nb)>::_M_do_find_first().

  size_t _Find_next (size_t __prev) const [inline, inherited]

Finds the index of the next 'on' bit after prev.

Returns:
    The index of the next bit set, or size() if not found.

Parameters:
    prev Where to start searching.

See also:
    _Find_first

Definition at line 1140 of file bitset.

References _Base_bitset< _GLIBCXX_BITSET_WORDS(_Nb)>::_M_do_find_next().

  bitset<_Nb>& _Unchecked_set (size_t __pos) [inline, inherited]

These versions of single-bit set, reset, flip, and test are extensions from the SGI version. They do no range checking.

Definition at line 857 of file bitset.

References _Base_bitset< _GLIBCXX_BITSET_WORDS(_Nb)>::_M_getword(), and _Base_bitset< _GLIBCXX_BITSET_WORDS(_Nb)>::_S_maskbit().

Referenced by bitset::set().

  unary_compose<_Operation1, _Operation2> __gnu_cxx::compose1 (const _Operation1 & __fn1, const _Operation2 & __fn2) [inline]

An SGI extension .

Definition at line 148 of file ext/functional.

  binary_compose<_Operation1, _Operation2, _Operation3> __gnu_cxx::compose2 (const _Operation1 & __fn1, const _Operation2 & __fn2, const _Operation3 & __fn3) [inline]

An SGI extension .

Definition at line 175 of file ext/functional.

  constant_void_fun<_Result> __gnu_cxx::constant0 (const _Result & __val) [inline]

An SGI extension .

Definition at line 329 of file ext/functional.

  constant_unary_fun<_Result, _Result> __gnu_cxx::constant1 (const _Result & __val) [inline]

An SGI extension .

Definition at line 335 of file ext/functional.

  constant_binary_fun<_Result,_Result,_Result> __gnu_cxx::constant2 (const _Result & __val) [inline]

An SGI extension .

Definition at line 341 of file ext/functional.

  pair<_InputIterator, _OutputIterator> __gnu_cxx::copy_n (_InputIterator __first, _Size __count, _OutputIterator __result) [inline]

Copies the range [first,first+count) into [result,result+count).

Parameters:
    first An input iterator.
    count The number of elements to copy.
    result An output iterator.

Returns:
    A std::pair composed of first+count and result+count.

This is an SGI extension. This inline function will boil down to a call to memmove whenever possible. Failing that, if random access iterators are passed, then the loop count will be known (and therefore a candidate for compiler optimizations such as unrolling).

Definition at line 124 of file ext/algorithm.

References __gnu_cxx::__copy_n(), __glibcxx_function_requires, and std::__iterator_category().

  _Tp __gnu_cxx::identity_element (std::multiplies< _Tp >) [inline]

An SGI extension .

Definition at line 96 of file ext/functional.

  _Tp __gnu_cxx::identity_element (std::plus< _Tp >) [inline]

An SGI extension .

Definition at line 90 of file ext/functional.

  void __gnu_cxx::iota (_ForwardIter __first, _ForwardIter __last, _Tp __value)

This is an SGI extension.

Todo
    Doc me! See docs/doxygen/TODO and http://gcc.gnu.org/ml/libstdc++/2002-02/msg00003.html for more.

Definition at line 138 of file ext/numeric.

References __glibcxx_function_requires.

  bool __gnu_cxx::is_heap (_RandomAccessIterator __first, _RandomAccessIterator __last, _StrictWeakOrdering __comp) [inline]

This is an SGI extension.

Todo
    Doc me! See docs/doxygen/TODO and http://gcc.gnu.org/ml/libstdc++/2002-02/msg00003.html for more.

Definition at line 456 of file ext/algorithm.

References __glibcxx_function_requires, and std::__is_heap().

  bool __gnu_cxx::is_heap (_RandomAccessIterator __first, _RandomAccessIterator __last) [inline]

This is an SGI extension.

Todo
    Doc me! See docs/doxygen/TODO and http://gcc.gnu.org/ml/libstdc++/2002-02/msg00003.html for more.

Definition at line 437 of file ext/algorithm.

References __glibcxx_function_requires, and std::__is_heap().

  bool __gnu_cxx::is_sorted (_ForwardIterator __first, _ForwardIterator __last, _StrictWeakOrdering __comp)

This is an SGI extension.

Todo
    Doc me! See docs/doxygen/TODO and http://gcc.gnu.org/ml/libstdc++/2002-02/msg00003.html for more.

Definition at line 506 of file ext/algorithm.

References __glibcxx_function_requires.

  bool __gnu_cxx::is_sorted (_ForwardIterator __first, _ForwardIterator __last)

This is an SGI extension.

Todo
    Doc me! See docs/doxygen/TODO and http://gcc.gnu.org/ml/libstdc++/2002-02/msg00003.html for more.

Definition at line 481 of file ext/algorithm.

References __glibcxx_function_requires.

  int __gnu_cxx::lexicographical_compare_3way (_InputIterator1 __first1, _InputIterator1 __last1, _InputIterator2 __first2, _InputIterator2 __last2)

memcmp on steroids.

Parameters:
    first1 An input iterator.
    last1 An input iterator.
    first2 An input iterator.
    last2 An input iterator.

Returns:
    An int, as with memcmp.

The return value will be less than zero if the first range is 'lexigraphically less than' the second, greater than zero if the second range is 'lexigraphically less than' the first, and zero otherwise. This is an SGI extension.

Definition at line 203 of file ext/algorithm.

References __glibcxx_function_requires, and __gnu_cxx::__lexicographical_compare_3way().

  _Tp __gnu_cxx::power (_Tp __x, _Integer __n) [inline]

This is an SGI extension.

Todo
    Doc me! See docs/doxygen/TODO and http://gcc.gnu.org/ml/libstdc++/2002-02/msg00003.html for more.

Definition at line 127 of file ext/numeric.

References __gnu_cxx::__power().

  _Tp __gnu_cxx::power (_Tp __x, _Integer __n, _MonoidOperation __monoid_op) [inline]

This is an SGI extension.

Todo
    Doc me! See docs/doxygen/TODO and http://gcc.gnu.org/ml/libstdc++/2002-02/msg00003.html for more.

Definition at line 117 of file ext/numeric.

References __gnu_cxx::__power().

Referenced by rope::rope().

  _RandomAccessIterator __gnu_cxx::random_sample (_InputIterator __first, _InputIterator __last, _RandomAccessIterator __out_first, _RandomAccessIterator __out_last, _RandomNumberGenerator & __rand) [inline]

This is an SGI extension.

Todo
    Doc me! See docs/doxygen/TODO and http://gcc.gnu.org/ml/libstdc++/2002-02/msg00003.html for more.

Definition at line 413 of file ext/algorithm.

References __glibcxx_function_requires, and __gnu_cxx::__random_sample().

  _RandomAccessIterator __gnu_cxx::random_sample (_InputIterator __first, _InputIterator __last, _RandomAccessIterator __out_first, _RandomAccessIterator __out_last) [inline]

This is an SGI extension.

Todo
    Doc me! See docs/doxygen/TODO and http://gcc.gnu.org/ml/libstdc++/2002-02/msg00003.html for more.

Definition at line 390 of file ext/algorithm.

References __glibcxx_function_requires, and __gnu_cxx::__random_sample().

  _OutputIterator __gnu_cxx::random_sample_n (_ForwardIterator __first, _ForwardIterator __last, _OutputIterator __out, const _Distance __n, _RandomNumberGenerator & __rand)

This is an SGI extension.

Todo
    Doc me! See docs/doxygen/TODO and http://gcc.gnu.org/ml/libstdc++/2002-02/msg00003.html for more.

Definition at line 303 of file ext/algorithm.

References __glibcxx_function_requires, std::distance(), and std::min().

  _OutputIterator __gnu_cxx::random_sample_n (_ForwardIterator __first, _ForwardIterator __last, _OutputIterator __out, const _Distance __n)

This is an SGI extension.

Todo
    Doc me! See docs/doxygen/TODO and http://gcc.gnu.org/ml/libstdc++/2002-02/msg00003.html for more.

Definition at line 269 of file ext/algorithm.

References __glibcxx_function_requires, std::distance(), and std::min().

  pair<_InputIter, _ForwardIter> __gnu_cxx::uninitialized_copy_n (_InputIter __first, _Size __count, _ForwardIter __result) [inline]

Copies the range [first,last) into result.

Parameters:
    first An input iterator.
    last An input iterator.
    result An output iterator.

Returns:
    result + (first - last)

Like copy(), but does not require an initialized output range.

Definition at line 126 of file ext/memory.

References std::__iterator_category(), and __gnu_cxx::__uninitialized_copy_n().

Referenced by __gnu_cxx::__uninitialized_copy_n_a(), rope::_S_destr_leaf_concat_char_iter(), and _Rope_RopeSubstring::operator()().