Quotient::asKeyValueRange< T > Class Template Reference

An adaptor for Qt (hash-)maps to make them iterable in STL style. More...

#include <util.h>

Public Member Functions
	asKeyValueRange (T data)
auto	begin ()
auto	end ()
auto	begin () const
auto	end () const

Detailed Description

template<typename T>
class Quotient::asKeyValueRange< T >

An adaptor for Qt (hash-)maps to make them iterable in STL style.

QMap/QHash container iterators returned by begin() and end() dereference to values, unlike STL where similar iterators dereference to key-value pairs. It is a problem in range-for if you want to also access map keys. This adaptor allows to use range-for syntax with access to both keys and values in QMap/QHash containers. Just use for (auto&& [key, value] : asKeyValueRange(myMap) instead of for (auto&& value : myMap).

Note

When an rvalue is passed as the constructor argument, asKeyValueRange shallow-copies the map object to ensure its lifetime is maintained throughout the loop; with lvalues, no copying occurs, assuming that the map object outlives the range-for loop

Definition at line 184 of file util.h.

Constructor & Destructor Documentation

asKeyValueRange()

template<typename T >

Quotient::asKeyValueRange< T >::asKeyValueRange ( T  data )

inlineexplicit

Definition at line 187 of file util.h.

Member Function Documentation

begin() [1/2]

template<typename T >

auto Quotient::asKeyValueRange< T >::begin ( )

inline

Definition at line 191 of file util.h.

begin() [2/2]

template<typename T >

auto Quotient::asKeyValueRange< T >::begin ( ) const

inline

Definition at line 199 of file util.h.

end() [1/2]

template<typename T >

auto Quotient::asKeyValueRange< T >::end ( )

inline

Definition at line 195 of file util.h.

end() [2/2]

template<typename T >

auto Quotient::asKeyValueRange< T >::end ( ) const

inline

Definition at line 200 of file util.h.

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

• Quotient/util.h