Implement P0253R1: Fixing a design mistake in the searchers interface.
git-svn-id: https://llvm.org/svn/llvm-project/libcxx/trunk@262928 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/include/algorithm b/include/algorithm
index 7dba11e..f439396 100644
--- a/include/algorithm
+++ b/include/algorithm
@@ -1421,20 +1421,20 @@
// search
template <class _BinaryPredicate, class _ForwardIterator1, class _ForwardIterator2>
-_ForwardIterator1
+pair<_ForwardIterator1, _ForwardIterator1>
__search(_ForwardIterator1 __first1, _ForwardIterator1 __last1,
_ForwardIterator2 __first2, _ForwardIterator2 __last2, _BinaryPredicate __pred,
forward_iterator_tag, forward_iterator_tag)
{
if (__first2 == __last2)
- return __first1; // Everything matches an empty sequence
+ return make_pair(__first1, __first1); // Everything matches an empty sequence
while (true)
{
// Find first element in sequence 1 that matchs *__first2, with a mininum of loop checks
while (true)
{
if (__first1 == __last1) // return __last1 if no element matches *__first2
- return __last1;
+ return make_pair(__last1, __last1);
if (__pred(*__first1, *__first2))
break;
++__first1;
@@ -1445,9 +1445,9 @@
while (true)
{
if (++__m2 == __last2) // If pattern exhausted, __first1 is the answer (works for 1 element pattern)
- return __first1;
+ return make_pair(__first1, __m1);
if (++__m1 == __last1) // Otherwise if source exhaused, pattern not found
- return __last1;
+ return make_pair(__last1, __last1);
if (!__pred(*__m1, *__m2)) // if there is a mismatch, restart with a new __first1
{
++__first1;
@@ -1458,20 +1458,21 @@
}
template <class _BinaryPredicate, class _RandomAccessIterator1, class _RandomAccessIterator2>
-_LIBCPP_CONSTEXPR_AFTER_CXX11 _RandomAccessIterator1
+_LIBCPP_CONSTEXPR_AFTER_CXX11
+pair<_RandomAccessIterator1, _RandomAccessIterator1>
__search(_RandomAccessIterator1 __first1, _RandomAccessIterator1 __last1,
- _RandomAccessIterator2 __first2, _RandomAccessIterator2 __last2, _BinaryPredicate __pred,
+ _RandomAccessIterator2 __first2, _RandomAccessIterator2 __last2, _BinaryPredicate __pred,
random_access_iterator_tag, random_access_iterator_tag)
{
- typedef typename std::iterator_traits<_RandomAccessIterator1>::difference_type _D1;
- typedef typename std::iterator_traits<_RandomAccessIterator2>::difference_type _D2;
+ typedef typename iterator_traits<_RandomAccessIterator1>::difference_type _D1;
+ typedef typename iterator_traits<_RandomAccessIterator2>::difference_type _D2;
// Take advantage of knowing source and pattern lengths. Stop short when source is smaller than pattern
- _D2 __len2 = __last2 - __first2;
+ const _D2 __len2 = __last2 - __first2;
if (__len2 == 0)
- return __first1;
- _D1 __len1 = __last1 - __first1;
+ return make_pair(__first1, __first1);
+ const _D1 __len1 = __last1 - __first1;
if (__len1 < __len2)
- return __last1;
+ return make_pair(__last1, __last1);
const _RandomAccessIterator1 __s = __last1 - (__len2 - 1); // Start of pattern match can't go beyond here
while (true)
{
@@ -1479,7 +1480,7 @@
while (true)
{
if (__first1 == __s)
- return __last1;
+ return make_pair(__last1, __last1);
if (__pred(*__first1, *__first2))
break;
++__first1;
@@ -1511,7 +1512,7 @@
if (__pred(*__first1, *__first2))
break;
case 0:
- return __last1;
+ return make_pair(__last1, __last1);
}
__phase2:
#endif // !_LIBCPP_UNROLL_LOOPS
@@ -1521,7 +1522,7 @@
while (true)
{
if (++__m2 == __last2)
- return __first1;
+ return make_pair(__first1, __first1 + __len2);
++__m1; // no need to check range on __m1 because __s guarantees we have enough source
if (!__pred(*__m1, *__m2))
{
@@ -1561,7 +1562,7 @@
if (!__pred(*__m1, *__m2))
break;
case 0:
- return __first1;
+ return make_pair(__first1, __first1 + __len2);
}
__continue:
++__first1;
@@ -1577,8 +1578,9 @@
{
return _VSTD::__search<typename add_lvalue_reference<_BinaryPredicate>::type>
(__first1, __last1, __first2, __last2, __pred,
- typename std::iterator_traits<_ForwardIterator1>::iterator_category(),
- typename std::iterator_traits<_ForwardIterator2>::iterator_category());
+ typename iterator_traits<_ForwardIterator1>::iterator_category(),
+ typename iterator_traits<_ForwardIterator2>::iterator_category())
+ .first;
}
template <class _ForwardIterator1, class _ForwardIterator2>
@@ -1587,8 +1589,8 @@
search(_ForwardIterator1 __first1, _ForwardIterator1 __last1,
_ForwardIterator2 __first2, _ForwardIterator2 __last2)
{
- typedef typename std::iterator_traits<_ForwardIterator1>::value_type __v1;
- typedef typename std::iterator_traits<_ForwardIterator2>::value_type __v2;
+ typedef typename iterator_traits<_ForwardIterator1>::value_type __v1;
+ typedef typename iterator_traits<_ForwardIterator2>::value_type __v2;
return _VSTD::search(__first1, __last1, __first2, __last2, __equal_to<__v1, __v2>());
}
diff --git a/include/experimental/algorithm b/include/experimental/algorithm
index ffaa793..3902111 100644
--- a/include/experimental/algorithm
+++ b/include/experimental/algorithm
@@ -53,7 +53,7 @@
template <class _ForwardIterator, class _Searcher>
_LIBCPP_INLINE_VISIBILITY
_ForwardIterator search(_ForwardIterator __f, _ForwardIterator __l, const _Searcher &__s)
-{ return __s(__f, __l); }
+{ return __s(__f, __l).first; }
template <class _PopulationIterator, class _SampleIterator, class _Distance,
diff --git a/include/experimental/functional b/include/experimental/functional
index c7a7869..75fc8e9 100644
--- a/include/experimental/functional
+++ b/include/experimental/functional
@@ -119,9 +119,12 @@
template <typename _ForwardIterator2>
_LIBCPP_INLINE_VISIBILITY
- _ForwardIterator2 operator () (_ForwardIterator2 __f, _ForwardIterator2 __l) const
+ pair<_ForwardIterator2, _ForwardIterator2>
+ operator () (_ForwardIterator2 __f, _ForwardIterator2 __l) const
{
- return _VSTD::search(__f, __l, __first_, __last_, __pred_);
+ return _VSTD::__search(__f, __l, __first_, __last_, __pred_,
+ typename _VSTD::iterator_traits<_ForwardIterator>::iterator_category(),
+ typename _VSTD::iterator_traits<_ForwardIterator2>::iterator_category());
}
private:
@@ -233,7 +236,7 @@
}
template <typename _RandomAccessIterator2>
- _RandomAccessIterator2
+ pair<_RandomAccessIterator2, _RandomAccessIterator2>
operator ()(_RandomAccessIterator2 __f, _RandomAccessIterator2 __l) const
{
static_assert ( std::is_same<
@@ -242,12 +245,12 @@
>::value,
"Corpus and Pattern iterators must point to the same type" );
- if (__f == __l ) return __l; // empty corpus
- if (__first_ == __last_) return __f; // empty pattern
+ if (__f == __l ) return make_pair(__l, __l); // empty corpus
+ if (__first_ == __last_) return make_pair(__f, __f); // empty pattern
// If the pattern is larger than the corpus, we can't find it!
if ( __pattern_length_ > _VSTD::distance (__f, __l))
- return __l;
+ return make_pair(__l, __l);
// Do the search
return this->__search(__f, __l);
@@ -262,7 +265,8 @@
shared_ptr<vector<difference_type>> __suffix_;
template <typename _RandomAccessIterator2>
- _RandomAccessIterator2 __search(_RandomAccessIterator2 __f, _RandomAccessIterator2 __l) const
+ pair<_RandomAccessIterator2, _RandomAccessIterator2>
+ __search(_RandomAccessIterator2 __f, _RandomAccessIterator2 __l) const
{
_RandomAccessIterator2 __cur = __f;
const _RandomAccessIterator2 __last = __l - __pattern_length_;
@@ -278,7 +282,7 @@
__j--;
// We matched - we're done!
if ( __j == 0 )
- return __cur;
+ return make_pair(__cur, __cur + __pattern_length_);
}
// Since we didn't match, figure out how far to skip forward
@@ -290,7 +294,7 @@
__cur += __suffix[ __j ];
}
- return __l; // We didn't find anything
+ return make_pair(__l, __l); // We didn't find anything
}
@@ -384,8 +388,8 @@
}
}
- template <typename _RandomAccessIterator2>
- _RandomAccessIterator2
+ template <typename _RandomAccessIterator2>
+ pair<_RandomAccessIterator2, _RandomAccessIterator2>
operator ()(_RandomAccessIterator2 __f, _RandomAccessIterator2 __l) const
{
static_assert ( std::is_same<
@@ -394,12 +398,12 @@
>::value,
"Corpus and Pattern iterators must point to the same type" );
- if (__f == __l ) return __l; // empty corpus
- if (__first_ == __last_) return __f; // empty pattern
+ if (__f == __l ) return make_pair(__l, __l); // empty corpus
+ if (__first_ == __last_) return make_pair(__f, __f); // empty pattern
// If the pattern is larger than the corpus, we can't find it!
if ( __pattern_length_ > _VSTD::distance (__f, __l))
- return __l;
+ return make_pair(__l, __l);
// Do the search
return this->__search(__f, __l);
@@ -413,7 +417,8 @@
shared_ptr<skip_table_type> __skip_;
template <typename _RandomAccessIterator2>
- _RandomAccessIterator2 __search ( _RandomAccessIterator2 __f, _RandomAccessIterator2 __l ) const {
+ pair<_RandomAccessIterator2, _RandomAccessIterator2>
+ __search ( _RandomAccessIterator2 __f, _RandomAccessIterator2 __l ) const {
_RandomAccessIterator2 __cur = __f;
const _RandomAccessIterator2 __last = __l - __pattern_length_;
const skip_table_type & __skip = *__skip_.get();
@@ -427,12 +432,12 @@
__j--;
// We matched - we're done!
if ( __j == 0 )
- return __cur;
+ return make_pair(__cur, __cur + __pattern_length_);
}
__cur += __skip[__cur[__pattern_length_-1]];
}
- return __l;
+ return make_pair(__l, __l);
}
};
diff --git a/include/string b/include/string
index 9150244..004dc3d 100644
--- a/include/string
+++ b/include/string
@@ -982,7 +982,7 @@
const _CharT* __r =
_VSTD::__search(__p + __pos, __p + __sz,
__s, __s + __n, _Traits::eq,
- random_access_iterator_tag(), random_access_iterator_tag());
+ random_access_iterator_tag(), random_access_iterator_tag()).first;
if (__r == __p + __sz)
return __npos;
return static_cast<_SizeT>(__r - __p);