sequence_util.h File Reference

Utilities used by coveo::enumerable. More...

Go to the source code of this file.

Classes
struct	coveo::seq_element_traits< T >
	Traits class for elements in a sequence. More...
struct	coveo::seq_traits< Seq >
	Traits class for a sequence. More...
struct	coveo::is_enumerable< T >
	Traits class to identify enumerable objects. More...

Functions
template<typename C , typename Seq >
auto	coveo::try_reserve (C &cnt, const Seq &seq) -> typename std::enable_if< is_enumerable< Seq >::value, bool >::type
	Helper function to quickly reserve space in a container if possible. More...
template<typename Seq >
auto	coveo::try_get_size_delegate (const Seq &seq) -> typename std::enable_if< is_enumerable< Seq >::value, std::function< std::size_t()>>::type
	Helper function to get a fast size delegate if possible. More...
template<typename It >
auto	coveo::try_get_size_delegate_for_iterators (const It &beg, const It &end) -> typename std::enable_if< std::is_base_of< std::random_access_iterator_tag, typename std::iterator_traits< It >::iterator_category >::value, std::function< std::size_t()>>::type
	Helper function to get a fast size delegate from iterators if possible. More...

Detailed Description

Copyright

2016-2019, Coveo Solutions Inc. Distributed under the Apache License, Version 2.0 (see LICENSE).

Function Documentation

try_reserve()

template<typename C , typename Seq >

auto coveo::try_reserve	(	C &	cnt,
		const Seq &	seq
	)		-> typename std::enable_if<is_enumerable<Seq>::value, bool>::type

Attempts to reserve space in container cnt to hold as many elements as found in sequence seq. This is performed only if it's possible to do so "quickly".

• If seq is a coveo::enumerable, space is reserved by using its coveo::enumerable::size() method if coveo::enumerable::has_fast_size() returns true.
• If seq is a container with a size() method, space is reserved by using that method.
• If seq is a sequence that uses random-access iterators, space is reserved by using std::distance().
• Otherwise, space is not reserved.

Parameters

cnt	Container in which to reserve space.
seq	Sequence to use to try to reserve space for.

Returns

true if space has actually been reserved in cnt.

try_get_size_delegate()

template<typename Seq >

auto coveo::try_get_size_delegate

(

const Seq &

seq

)

-> typename std::enable_if<is_enumerable<Seq>::value, std::function<std::size_t()>>::type

Attempts to create a coveo::enumerable::size_delegate that can quickly calculate the number of elements found in sequence seq. A size delegate is returned only if it's possible to calculate the number of elements "quickly".

• If seq is a coveo::enumerable, its coveo::enumerable::size() method is used to produce the size delegate if coveo::enumerable::has_fast_size() returns true.
• If seq is a container with a size() method, a size delegate is produced using that method.
• If seq is a sequence that uses random-access iterators, a size delegate is produced by using std::distance().
• Otherwise, no size delegate is produced.

Parameters

seq	Sequence to calculate the number of elements of in order to produce the size delegate.

Returns

coveo::enumerable::size_delegate instance, or nullptr if it's not possible to quickly calculate the number of elements in seq.

See also

coveo::enumerable::size_delegate

try_get_size_delegate_for_iterators()

template<typename It >

auto coveo::try_get_size_delegate_for_iterators	(	const It &	beg,
		const It &	end
	)		-> typename std::enable_if<std::is_base_of<std::random_access_iterator_tag, typename std::iterator_traits<It>::iterator_category>::value, std::function<std::size_t()>>::type

Attempts to create a coveo::enumerable::size_delegate that can quickly calculate the number of elements in range [beg, end[. A size delegate is returned only if it's possible to calculate the number of elements "quickly".

• If beg and end are random-access iterators, a size delegate is produced by using std::distance().
• Otherwise, no size delegate is produced.

Parameters

beg	Iterator pointing at beginning of range.
end	Iterator pointing at end of range.

Returns

coveo::enumerable::size_delegate instance, or nullptr if it's not possible to quickly calculate the number of elements in [beg, end[

See also

coveo::enumerable::size_delegate