NAME¶

std::experimental::ranges::mismatch - std::experimental::ranges::mismatch

Synopsis¶

Defined in header <experimental/ranges/algorithm>
template< InputIterator I1, Sentinel<I1> S1, InputIterator I2,
Sentinel<I2> S2,

class Proj1 = ranges::identity, class Proj2 = ranges::identity,
class Pred = ranges::equal_to<> >
requires IndirectRelation<Pred, projected<I1, Proj1>, projected<I2, (1) (ranges TS)
Proj2>>
auto mismatch(I1 first1, S1 last1, I2 first2, S2 last2, Pred pred =
Pred{},
Proj1 proj1 = Proj1{}, Proj2 proj2 = Proj2{})

-> ranges::tagged_pair<tag::in1(I1), tag::in2(I2)>;
template< InputRange R1, InputRange R2,

class Proj1 = ranges::identity, class Proj2 = ranges::identity,
class Pred = ranges::equal_to<> >
requires IndirectRelation<Pred, projected<ranges::iterator_t<R1>,
Proj1>, (2) (ranges TS)
projected<ranges::iterator_t<R2>, Proj2>>
auto mismatch(R1&& r1, R2&& r2, Pred pred = Pred{},
Proj1 proj1 = Proj1{}, Proj2 proj2 = Proj2{})
-> ranges::tagged_pair<tag::in1(ranges::safe_iterator_t<R1>),

tag::in2(ranges::safe_iterator_t<R2>)>;
template< InputIterator I1, Sentinel<I1> S1, class I2,

class Pred = ranges::equal_to<>,
class Proj1 = ranges::identity, class Proj2 = ranges::identity >
requires InputIterator<std::decay_t<I2>> && !Range<I2> &&
IndirectRelation<Pred, projected<I1, Proj1>, (3) (ranges TS)
projected<std::decay_t<I2>, Proj2>> (deprecated)
auto mismatch(I1 first1, S1 last1, I2&& first2_, Pred pred =
Pred{},
Proj1 proj1 = Proj1{}, Proj2 proj2 = Proj2{})

-> ranges::tagged_pair<tag::in1(I1), tag::in2(std::decay_t<I2>)>;
template< InputRange R1, class I2, class Pred = ranges::equal_to<>,

class Proj1 = ranges::identity, class Proj2 = ranges::identity>
requires InputIterator<std::decay_t<I2>> && !Range<I2> &&
IndirectRelation<Pred, projected<ranges::iterator_t<R1>, Proj1>, (ranges TS)
projected<std::decay_t<I2>, Proj2>> (4) (deprecated)
auto mismatch(R1&& r1, I2&& first2_, Pred pred = Pred{},
Proj1 proj1 = Proj1{}, Proj2 proj2 = Proj2{})
-> ranges::tagged_pair<tag::in1(ranges::safe_iterator_t<Rng1>),

tag::in2(std::decay_t<I2>)>;

1) Returns the first mismatching pair of elements from two ranges: one defined by
[first1, last1) and another defined by [first2, last2).
2) Same as (1), but uses r1 as the first source range and r2 as the second source
range, as if using ranges::begin(r1) as first1, ranges::end(r1) as last1,
ranges::begin(r2) as first2, and ranges::end(r2) as last2.
3) Same as (1), but behaves as if first2 is std::decay_t<I2> first2 =
std::forward<I2>(first2_); and last2 is ranges::unreachable{}. The underlying
algorithm never increments first2 more than last1 - first1 times.
4) Same as (3), but uses r1 as the first source range, as if using ranges::begin(r1)
as first1 and ranges::end(r1) as last1.

Elements are compared using pred to the projected elements of the two ranges, as if
by ranges::invoke(pred, ranges::invoke(proj1, *i), ranges::invoke(proj2, *j)).

Notwithstanding the declarations depicted above, the actual number and order of
template parameters for algorithm declarations is unspecified. Thus, if explicit
template arguments are used when calling an algorithm, the program is probably
non-portable.

Parameters¶

first1, last1 - the first range of the elements
r1 - the first range of the elements
first2, last2 - the second range of the elements
r2 - the second range of the elements
first2_ - the beginning of the second range of the elements
pred - predicate to apply to the projected elements
proj1 - projection to apply to the elements in the first range
proj2 - projection to apply to the elements in the second range

Return value¶

A tagged_pair object with iterators to the first two non-equal elements (the
iterator from the first range has the tag in1 and the iterator from the second range
has the tag in2).

If no mismatches are found when the comparison reaches last1 or last2, whichever
happens first, the pair holds the end iterator and the corresponding iterator from
the other range.

Complexity¶

At most last1 - first1 applications of the predicate and each projection.

Possible implementation¶

template< InputIterator I1, Sentinel<I1> S1, InputIterator I2, Sentinel<I2> S2,
class Proj1 = ranges::identity, class Proj2 = ranges::identity,
class Pred = ranges::equal_to<> >
requires IndirectRelation<Pred, projected<I1, Proj1>, projected<I2, Proj2>>
auto mismatch(I1 first1, S1 last1, I2 first2, S2 last2, Pred pred = Pred{},
Proj1 proj1 = Proj1{}, Proj2 proj2 = Proj2{})
-> ranges::tagged_pair<tag::in1(I1), tag::in2(I2)>
{
while (first1 != last1 && first2 != last2 &&
ranges::invoke(pred, ranges::invoke(proj1, *first1),
ranges::invoke(proj2, *first2))) {
++first1;
++first2;
}
return {first1, first2};
}

Example¶

This section is incomplete
Reason: no example

See also¶

mismatch finds the first position where two ranges differ
(function template)
equal determines if two sets of elements are the same
(function template)
find finds the first element satisfying specific criteria
find_if (function template)
find_if_not
returns true if one range is lexicographically less than
lexicographical_compare another
(function template)
search searches for a range of elements
(function template)