25
Ranges library
[ranges]
25.6
Range factories
[range.factories]
25.6.2
Empty view
[range.empty]
25.6.2.1
Overview
[range.empty.overview]
1
#
empty_
view
produces a view of no elements of a particular type
.
2
#
[
Example
1
:
auto
e
=
views
::
empty
<
int
>
;
static_assert
(
ranges
::
empty
(
e
)
)
;
static_assert
(
0
=
=
e
.
size
(
)
)
;
—
end example
]
25.6.2.2
Class template
empty_
view
[range.empty.view]
🔗
namespace
std
::
ranges
{
template
<
class
T
>
requires
is_object_v
<
T
>
class
empty_view
:
public
view_interface
<
empty_view
<
T
>
>
{
public
:
static
constexpr
T
*
begin
(
)
noexcept
{
return
nullptr
;
}
static
constexpr
T
*
end
(
)
noexcept
{
return
nullptr
;
}
static
constexpr
T
*
data
(
)
noexcept
{
return
nullptr
;
}
static
constexpr
size_t size
(
)
noexcept
{
return
0
;
}
static
constexpr
bool
empty
(
)
noexcept
{
return
true
;
}
}
;
}