#include <TextView.h>

Collaboration diagram for swoc::TransformView< X, V >:

Public Types
using	transform_type = X
	Export transform functor type.

using	source_view_type = V
	Export source view type.

using	source_value_type = std::remove_reference_t<decltype(*source_iterator{})>

using	value_type = std::invoke_result_t<transform_type, source_value_type>
	Result type of calling the transform on an element of the source view.

using	iterator = self_type
	This class serves as its own iterator.

Public Member Functions
	TransformView (transform_type &&xf, source_view_type const &v)

	TransformView (transform_type const &xf, source_view_type const &v)

	TransformView (self_type const &that)=default
	Copy constructor.

	TransformView (self_type &&that)=default
	Move constructor.

self_type &	operator= (self_type const &that)=default
	Copy assignment.

self_type &	operator= (self_type &&that)=default
	Move assignment.

bool	operator== (self_type const &that) const
	Equality.

bool	operator!= (self_type const &that) const
	Inequality.

value_type	operator* () const
	Get the current element.

self_type &	operator++ ()
	Move to next element.

self_type	operator++ (int)
	Move to next element.

bool	empty () const
	Check if view is empty.

	operator bool () const
	Check if bool is not empty.

iterator	begin () const
	Iterator to first transformed character.

iterator	end () const
	Iterator past last transformed character.

Protected Member Functions
	TransformView (transform_type &&xf, source_iterator &&limit)
	Special constructor for making an empty instance to serve as the `end` iterator.

Protected Attributes
transform_type	_xf
	Per character transform functor.

source_iterator	_spot
	Current location in the source view.

source_iterator	_limit
	End of source view.

Detailed Description

template<typename X, typename V>
class swoc::TransformView< X, V >

A transform view.

Template Parameters

X	Transform functor type.
V	Source view type.

A transform view acts like a view on the original source view V with each element transformed by X.

This is used most commonly with std::string_view. For example, if the goal is to handle a piece of text as if it were lower case without changing the actual text, the following would make that possible.

std:::string_view source; // original text.

TransformView<int (*)(int) noexcept, std::string_view> xv(&tolower, source);

swoc::TransformView::TransformView

TransformView(transform_type &&xf, source_view_type const &v)

Definition TextView.h:1874

std

STL namespace.

To avoid having to figure out the exact signature of the transform, the convenience function transform_view_of is provide.

std::string_view source; // original text.

auto xv = transform_view_of(&tolower, source);

swoc::transform_view_of

TransformView< X, V > transform_view_of(X const &xf, V const &src)

Definition TextView.h:1933

This class supports iterators but those should be avoided as use of them makes extra copies of the instance which may be expensive if the functor is expensive. In cases where the functor is a function pointer or a lambda this isn't an issue.

Definition at line 1799 of file TextView.h.

Member Typedef Documentation

◆ iterator

template<typename X, typename V>

using swoc::TransformView< X, V >::iterator = self_type

This class serves as its own iterator.

Definition at line 1810 of file TextView.h.

◆ source_value_type

template<typename X, typename V>

using swoc::TransformView< X, V >::source_value_type = std::remove_reference_t<decltype(*source_iterator{})>

Definition at line 1806 of file TextView.h.

◆ source_view_type

template<typename X, typename V>

using swoc::TransformView< X, V >::source_view_type = V

Export source view type.

Definition at line 1805 of file TextView.h.

◆ transform_type

template<typename X, typename V>

using swoc::TransformView< X, V >::transform_type = X

Export transform functor type.

Definition at line 1804 of file TextView.h.

◆ value_type

template<typename X, typename V>

using swoc::TransformView< X, V >::value_type = std::invoke_result_t<transform_type, source_value_type>

Result type of calling the transform on an element of the source view.

Definition at line 1808 of file TextView.h.

Constructor & Destructor Documentation

◆ TransformView() [1/3]

template<typename X, typename V>

swoc::TransformView< X, V >::TransformView	(	transform_type &&	xf,
		source_view_type const &	v )

Construct a transform view using transform xf on source view v.

Parameters

xf	Transform instance.
v	Source view.

Definition at line 1874 of file TextView.h.

◆ TransformView() [2/3]

template<typename X, typename V>

swoc::TransformView< X, V >::TransformView	(	transform_type const &	xf,
		source_view_type const &	v )

Construct a transform view using transform xf on source view v.

Parameters

xf	Transform instance.
v	Source view.

Definition at line 1877 of file TextView.h.

◆ TransformView() [3/3]

template<typename X, typename V>

swoc::TransformView< X, V >::TransformView	(	transform_type &&	xf,
		source_iterator &&	limit )

inlineprotected

Special constructor for making an empty instance to serve as the end iterator.

Definition at line 1870 of file TextView.h.

Member Function Documentation

◆ begin()

template<typename X, typename V>

iterator swoc::TransformView< X, V >::begin ( ) const

inline

Iterator to first transformed character.

Definition at line 1855 of file TextView.h.

◆ empty()

template<typename X, typename V>

bool swoc::TransformView< X, V >::empty ( ) const

Check if view is empty.

Definition at line 1903 of file TextView.h.

◆ end()

template<typename X, typename V>

iterator swoc::TransformView< X, V >::end ( ) const

inline

Iterator past last transformed character.

Definition at line 1860 of file TextView.h.

◆ operator bool()

template<typename X, typename V>

swoc::TransformView< X, V >::operator bool ( ) const

explicit

Check if bool is not empty.

Definition at line 1907 of file TextView.h.

◆ operator!=()

template<typename X, typename V>

bool swoc::TransformView< X, V >::operator!= ( self_type const & that ) const

Inequality.

Definition at line 1919 of file TextView.h.

◆ operator*()

template<typename X, typename V>

auto swoc::TransformView< X, V >::operator* ( ) const

Get the current element.

Definition at line 1882 of file TextView.h.

◆ operator++() [1/2]

template<typename X, typename V>

auto swoc::TransformView< X, V >::operator++ ( )

Move to next element.

Definition at line 1888 of file TextView.h.

◆ operator++() [2/2]

template<typename X, typename V>

auto swoc::TransformView< X, V >::operator++ ( int )

Move to next element.

Definition at line 1895 of file TextView.h.

◆ operator==()

template<typename X, typename V>

bool swoc::TransformView< X, V >::operator== ( self_type const & that ) const

Equality.

Definition at line 1913 of file TextView.h.

Member Data Documentation

◆ _limit

template<typename X, typename V>

source_iterator swoc::TransformView< X, V >::_limit

protected

End of source view.

Definition at line 1867 of file TextView.h.

◆ _spot

template<typename X, typename V>

source_iterator swoc::TransformView< X, V >::_spot

protected

Current location in the source view.

Definition at line 1866 of file TextView.h.

◆ _xf

template<typename X, typename V>

transform_type swoc::TransformView< X, V >::_xf

protected

Per character transform functor.

Definition at line 1865 of file TextView.h.

The documentation for this class was generated from the following file:

TextView.h

Public Types

Public Member Functions

Protected Member Functions

Protected Attributes

Detailed Description

Member Typedef Documentation

◆ iterator

◆ source_value_type

◆ source_view_type

◆ transform_type

◆ value_type

Constructor & Destructor Documentation

◆ TransformView() [1/3]

◆ TransformView() [2/3]

◆ TransformView() [3/3]

Member Function Documentation

◆ begin()

◆ empty()

◆ end()

◆ operator bool()

◆ operator!=()

◆ operator*()

◆ operator++() [1/2]

◆ operator++() [2/2]

◆ operator==()

Member Data Documentation

◆ _limit

◆ _spot

◆ _xf