SGIextensions(3cxx) SGIextensions(3cxx)
NAME
SGIextensions - SGI
SYNOPSIS
Classes
struct __gnu_cxx::project1st< _Arg1, _Arg2 >
An SGI extension .
struct __gnu_cxx::project2nd< _Arg1, _Arg2 >
An SGI extension .
struct __gnu_cxx::select1st< _Pair >
An SGI extension .
struct __gnu_cxx::select2nd< _Pair >
An SGI extension .
Functions
template<typename _Tp > const _Tp & __gnu_cxx::__median (const _Tp
&__a, const _Tp &__b, const _Tp &__c)
Find the median of three values.
template<typename _Tp , typename _Compare > const _Tp &
__gnu_cxx::__median (const _Tp &__a, const _Tp &__b, const _Tp
&__c, _Compare __comp)
Find the median of three values using a predicate for comparison.
size_t std::bitset< _Nb >::_Find_first () const noexcept
Finds the index of the first 'on' bit.
size_t std::bitset< _Nb >::_Find_next (size_t __prev) const noexcept
Finds the index of the next 'on' bit after prev.
template<class _Operation1 , class _Operation2 > unary_compose<
_Operation1, _Operation2 > __gnu_cxx::compose1 (const _Operation1
&__fn1, const _Operation2 &__fn2)
An SGI extension .
template<class _Operation1 , class _Operation2 , class _Operation3 >
binary_compose< _Operation1, _Operation2, _Operation3 >
__gnu_cxx::compose2 (const _Operation1 &__fn1, const _Operation2
&__fn2, const _Operation3 &__fn3)
An SGI extension .
template<class _Result > constant_void_fun< _Result >
__gnu_cxx::constant0 (const _Result &__val)
An SGI extension .
template<class _Result > constant_unary_fun< _Result, _Result >
__gnu_cxx::constant1 (const _Result &__val)
An SGI extension .
template<class _Result > constant_binary_fun< _Result, _Result, _Result
> __gnu_cxx::constant2 (const _Result &__val)
An SGI extension .
template<typename _InputIterator , typename _Size , typename
_OutputIterator > std::pair< _InputIterator, _OutputIterator >
__gnu_cxx::copy_n (_InputIterator __first, _Size __count,
_OutputIterator __result)
Copies the range [first,first+count) into [result,result+count).
template<typename _InputIterator , typename _Distance > void
__gnu_cxx::distance (_InputIterator __first, _InputIterator __last,
_Distance &__n)
template<class _Tp > _Tp __gnu_cxx::identity_element (std::multiplies<
_Tp >)
An SGI extension .
template<class _Tp > _Tp __gnu_cxx::identity_element (std::plus< _Tp >)
An SGI extension .
template<typename _InputIterator1 , typename _InputIterator2 > int
__gnu_cxx::lexicographical_compare_3way (_InputIterator1 __first1,
_InputIterator1 __last1, _InputIterator2 __first2, _InputIterator2
__last2)
memcmp on steroids.
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 >
_RandomAccessIterator __gnu_cxx::random_sample (_InputIterator
__first, _InputIterator __last, _RandomAccessIterator __out_first,
_RandomAccessIterator __out_last)
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 _ForwardIterator , typename _OutputIterator ,
typename _Distance > _OutputIterator __gnu_cxx::random_sample_n
(_ForwardIterator __first, _ForwardIterator __last, _OutputIterator
__out, const _Distance __n)
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 _InputIter , typename _Size , typename _ForwardIter >
std::pair< _InputIter, _ForwardIter >
__gnu_cxx::uninitialized_copy_n (_InputIter __first, _Size __count,
_ForwardIter __result)
Copies the range [first,last) into result.
bitset< _Nb > & std::bitset< _Nb >::_Unchecked_set (size_t __pos)
noexcept
bitset< _Nb > & std::bitset< _Nb >::_Unchecked_set (size_t __pos, int
__val) noexcept
bitset< _Nb > & std::bitset< _Nb >::_Unchecked_reset (size_t __pos)
noexcept
bitset< _Nb > & std::bitset< _Nb >::_Unchecked_flip (size_t __pos)
noexcept
constexpr bool std::bitset< _Nb >::_Unchecked_test (size_t __pos) const
noexcept
Detailed Description
Because libstdc++ 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 compose2 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.
Function Documentation
template<typename _Tp > const _Tp& __gnu_cxx::__median (const _Tp & __a,
const _Tp & __b, const _Tp & __c)
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.
template<typename _Tp , typename _Compare > const _Tp& __gnu_cxx::__median
(const _Tp & __a, const _Tp & __b, const _Tp & __c, _Compare __comp)
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.
template<size_t _Nb> size_t std::bitset< _Nb >::_Find_first () const
[inline], [noexcept]
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
template<size_t _Nb> size_t std::bitset< _Nb >::_Find_next (size_t __prev)
const [inline], [noexcept]
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
template<size_t _Nb> bitset<_Nb>& std::bitset< _Nb >::_Unchecked_flip
(size_t __pos) [inline], [noexcept]
These versions of single-bit set, reset, flip, and test are extensions
from the SGI version. They do no range checking.
template<size_t _Nb> bitset<_Nb>& std::bitset< _Nb >::_Unchecked_reset
(size_t __pos) [inline], [noexcept]
These versions of single-bit set, reset, flip, and test are extensions
from the SGI version. They do no range checking.
template<size_t _Nb> bitset<_Nb>& std::bitset< _Nb >::_Unchecked_set
(size_t __pos) [inline], [noexcept]
These versions of single-bit set, reset, flip, and test are extensions
from the SGI version. They do no range checking.
template<size_t _Nb> bitset<_Nb>& std::bitset< _Nb >::_Unchecked_set
(size_t __pos, int __val) [inline], [noexcept]
These versions of single-bit set, reset, flip, and test are extensions
from the SGI version. They do no range checking.
template<size_t _Nb> constexpr bool std::bitset< _Nb >::_Unchecked_test
(size_t __pos) const [inline], [constexpr], [noexcept]
These versions of single-bit set, reset, flip, and test are extensions
from the SGI version. They do no range checking.
template<class _Operation1 , class _Operation2 > unary_compose<_Operation1,
_Operation2> __gnu_cxx::compose1 (const _Operation1 & __fn1, const
_Operation2 & __fn2) [inline]
An SGI extension .
template<class _Operation1 , class _Operation2 , class _Operation3 >
binary_compose<_Operation1, _Operation2, _Operation3>
__gnu_cxx::compose2 (const _Operation1 & __fn1, const _Operation2 &
__fn2, const _Operation3 & __fn3) [inline]
An SGI extension .
template<class _Result > constant_void_fun<_Result> __gnu_cxx::constant0
(const _Result & __val) [inline]
An SGI extension .
template<class _Result > constant_unary_fun<_Result, _Result>
__gnu_cxx::constant1 (const _Result & __val) [inline]
An SGI extension .
template<class _Result > constant_binary_fun<_Result,_Result,_Result>
__gnu_cxx::constant2 (const _Result & __val) [inline]
An SGI extension .
template<typename _InputIterator , typename _Size , typename
_OutputIterator > std::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).
template<typename _InputIterator , typename _Distance > void
__gnu_cxx::distance (_InputIterator __first, _InputIterator __last,
_Distance & __n) [inline]
This is an SGI extension.
Todo
Needs documentation! See
http://gcc.gnu.org/onlinedocs/libstdc++/manual/documentation_style.html
template<class _Tp > _Tp __gnu_cxx::identity_element (std::multiplies< _Tp
>) [inline]
An SGI extension .
template<class _Tp > _Tp __gnu_cxx::identity_element (std::plus< _Tp >)
[inline]
An SGI extension .
template<typename _InputIterator1 , typename _InputIterator2 > 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.
template<typename _Tp , typename _Integer > _Tp __gnu_cxx::power (_Tp __x,
_Integer __n) [inline]
This is an SGI extension.
Todo
Needs documentation! See
http://gcc.gnu.org/onlinedocs/libstdc++/manual/documentation_style.html
template<typename _Tp , typename _Integer , typename _MonoidOperation > _Tp
__gnu_cxx::power (_Tp __x, _Integer __n, _MonoidOperation __monoid_op)
[inline]
This is an SGI extension.
Todo
Needs documentation! See
http://gcc.gnu.org/onlinedocs/libstdc++/manual/documentation_style.html
template<typename _InputIterator , typename _RandomAccessIterator >
_RandomAccessIterator __gnu_cxx::random_sample (_InputIterator __first,
_InputIterator __last, _RandomAccessIterator __out_first,
_RandomAccessIterator __out_last) [inline]
This is an SGI extension.
Todo
Needs documentation! See
http://gcc.gnu.org/onlinedocs/libstdc++/manual/documentation_style.html
template<typename _InputIterator , typename _RandomAccessIterator ,
typename _RandomNumberGenerator > _RandomAccessIterator
__gnu_cxx::random_sample (_InputIterator __first, _InputIterator
__last, _RandomAccessIterator __out_first, _RandomAccessIterator
__out_last, _RandomNumberGenerator & __rand) [inline]
This is an SGI extension.
Todo
Needs documentation! See
http://gcc.gnu.org/onlinedocs/libstdc++/manual/documentation_style.html
template<typename _ForwardIterator , typename _OutputIterator , typename
_Distance > _OutputIterator __gnu_cxx::random_sample_n
(_ForwardIterator __first, _ForwardIterator __last, _OutputIterator
__out, const _Distance __n)
This is an SGI extension.
Todo
Needs documentation! See
http://gcc.gnu.org/onlinedocs/libstdc++/manual/documentation_style.html
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)
This is an SGI extension.
Todo
Needs documentation! See
http://gcc.gnu.org/onlinedocs/libstdc++/manual/documentation_style.html
template<typename _InputIter , typename _Size , typename _ForwardIter >
std::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.
__count Length
__result An output iterator.
Returns
__result + (__first + __count)
Like copy(), but does not require an initialized output range.
Author
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