Struct qt_core::q_hash_of_q_string_q_variant::ConstIterator

#[repr(C)]
pub struct ConstIterator { /* private fields */ }

The QHash::const_iterator class provides an STL-style const iterator for QHash and QMultiHash.

C++ class: QHash<QString, QVariant>::const_iterator.

C++ documentation:

The QHash::const_iterator class provides an STL-style const iterator for QHash and QMultiHash.

QHash features both STL-style iterators and Java-style iterators. The STL-style iterators are more low-level and more cumbersome to use; on the other hand, they are slightly faster and, for developers who already know STL, have the advantage of familiarity.

QHash<Key, T>::const_iterator allows you to iterate over a QHash (or a QMultiHash). If you want to modify the QHash as you iterate over it, you must use QHash::iterator instead. It is generally good practice to use QHash::const_iterator on a non-const QHash as well, unless you need to change the QHash through the iterator. Const iterators are slightly faster, and can improve code readability.

The default QHash::const_iterator constructor creates an uninitialized iterator. You must initialize it using a QHash function like QHash::constBegin(), QHash::constEnd(), or QHash::find() before you can start iterating. Here's a typical loop that prints all the (key, value) pairs stored in a hash:

QHash<QString, int> hash;
hash.insert(“January”, 1);
hash.insert(“February”, 2);
...
hash.insert(“December”, 12);
QHash<QString, int>::const_iterator i;
for (i = hash.constBegin(); i != hash.constEnd(); ++i)
      cout << i.key() << “: “ << i.value() << endl;

Unlike QMap, which orders its items by key, QHash stores its items in an arbitrary order. The only guarantee is that items that share the same key (because they were inserted using QHash::insertMulti()) will appear consecutively, from the most recently to the least recently inserted value.

Multiple iterators can be used on the same hash. However, be aware that any modification performed directly on the QHash has the potential of dramatically changing the order in which the items are stored in the hash, as they might cause QHash to rehash its internal data structure. If you need to keep iterators over a long period of time, we recommend that you use QMap rather than QHash.

Warning: Iterators on implicitly shared containers do not work exactly like STL-iterators. You should avoid copying a container while iterators are active on that container. For more information, read Implicit sharing iterator problem.

Implementations

impl ConstIterator

pub unsafe fn add_assign(&self, j: c_int) -> Ref<ConstIterator>

Advances the iterator by j items.

Calls C++ function: QHash<QString, QVariant>::const_iterator& QHash<QString, QVariant>::const_iterator::operator+=(int j).

C++ documentation:

Advances the iterator by j items.

See also operator-=() and operator+().

pub unsafe fn copy_from( &self, other: impl CastInto<Ref<ConstIterator>> ) -> Ref<ConstIterator>

The QHash::const_iterator class provides an STL-style const iterator for QHash and QMultiHash.

Calls C++ function: QHash<QString, QVariant>::const_iterator& QHash<QString, QVariant>::const_iterator::operator=(const QHash<QString, QVariant>::const_iterator& other).

C++ documentation:

The QHash::const_iterator class provides an STL-style const iterator for QHash and QMultiHash.

QHash features both STL-style iterators and Java-style iterators. The STL-style iterators are more low-level and more cumbersome to use; on the other hand, they are slightly faster and, for developers who already know STL, have the advantage of familiarity.

QHash<Key, T>::const_iterator allows you to iterate over a QHash (or a QMultiHash). If you want to modify the QHash as you iterate over it, you must use QHash::iterator instead. It is generally good practice to use QHash::const_iterator on a non-const QHash as well, unless you need to change the QHash through the iterator. Const iterators are slightly faster, and can improve code readability.

The default QHash::const_iterator constructor creates an uninitialized iterator. You must initialize it using a QHash function like QHash::constBegin(), QHash::constEnd(), or QHash::find() before you can start iterating. Here's a typical loop that prints all the (key, value) pairs stored in a hash:

QHash<QString, int> hash;
hash.insert(“January”, 1);
hash.insert(“February”, 2);
...
hash.insert(“December”, 12);
QHash<QString, int>::const_iterator i;
for (i = hash.constBegin(); i != hash.constEnd(); ++i)
      cout << i.key() << “: “ << i.value() << endl;

Unlike QMap, which orders its items by key, QHash stores its items in an arbitrary order. The only guarantee is that items that share the same key (because they were inserted using QHash::insertMulti()) will appear consecutively, from the most recently to the least recently inserted value.

Multiple iterators can be used on the same hash. However, be aware that any modification performed directly on the QHash has the potential of dramatically changing the order in which the items are stored in the hash, as they might cause QHash to rehash its internal data structure. If you need to keep iterators over a long period of time, we recommend that you use QMap rather than QHash.

Warning: Iterators on implicitly shared containers do not work exactly like STL-iterators. You should avoid copying a container while iterators are active on that container. For more information, read Implicit sharing iterator problem.

pub unsafe fn dec(&self) -> Ref<ConstIterator>

The prefix -- operator (--it) makes the preceding item current and returns an iterator to the new current item.

Calls C++ function: QHash<QString, QVariant>::const_iterator& QHash<QString, QVariant>::const_iterator::operator--().

C++ documentation:

The prefix – operator (–it) makes the preceding item current and returns an iterator to the new current item.

Calling this function on QAssociativeIterable::begin() leads to undefined results.

See also operator++().

pub unsafe fn dec_postfix(&self, arg1: c_int) -> CppBox<ConstIterator>

This is an overloaded function.

Calls C++ function: QHash<QString, QVariant>::const_iterator QHash<QString, QVariant>::const_iterator::operator--(int arg1).

C++ documentation:

This is an overloaded function.

The postfix -- operator (it--) makes the preceding item current and returns an iterator to the previously current item.

pub unsafe fn inc(&self) -> Ref<ConstIterator>

The prefix ++ operator (++it) advances the iterator to the next item in the container and returns an iterator to the new current item.

Calls C++ function: QHash<QString, QVariant>::const_iterator& QHash<QString, QVariant>::const_iterator::operator++().

C++ documentation:

The prefix ++ operator (++it) advances the iterator to the next item in the container and returns an iterator to the new current item.

Calling this function on QAssociativeIterable::end() leads to undefined results.

See also operator--().

pub unsafe fn inc_postfix(&self, arg1: c_int) -> CppBox<ConstIterator>

This is an overloaded function.

Calls C++ function: QHash<QString, QVariant>::const_iterator QHash<QString, QVariant>::const_iterator::operator++(int arg1).

C++ documentation:

This is an overloaded function.

The postfix ++ operator (it++) advances the iterator to the next item in the container and returns an iterator to the previously current item.

pub unsafe fn indirection(&self) -> Ref<QVariant>

Returns the current value, converted to a QVariant.

Calls C++ function: const QVariant& QHash<QString, QVariant>::const_iterator::operator*() const.

C++ documentation:

Returns the current value, converted to a QVariant.

pub unsafe fn key(&self) -> Ref<QString>

Returns the current key, converted to a QVariant.

Calls C++ function: const QString& QHash<QString, QVariant>::const_iterator::key() const.

C++ documentation:

Returns the current key, converted to a QVariant.

pub unsafe fn new() -> CppBox<ConstIterator>

Constructs an uninitialized iterator.

Calls C++ function: [constructor] void QHash<QString, QVariant>::const_iterator::const_iterator().

C++ documentation:

Constructs an uninitialized iterator.

Functions like key(), value(), and operator++() must not be called on an uninitialized iterator. Use operator=() to assign a value to it before using it.

See also QHash::constBegin() and QHash::constEnd().

pub unsafe fn from_void(node: *mut c_void) -> CppBox<ConstIterator>

Calls C++ function: [constructor] void QHash<QString, QVariant>::const_iterator::const_iterator(void* node).

pub unsafe fn from_iterator( o: impl CastInto<Ref<Iterator>> ) -> CppBox<ConstIterator>

Constructs a copy of other.

Calls C++ function: [constructor] void QHash<QString, QVariant>::const_iterator::const_iterator(const QHash<QString, QVariant>::iterator& o).

C++ documentation:

Constructs a copy of other.

pub unsafe fn new_copy( other: impl CastInto<Ref<ConstIterator>> ) -> CppBox<ConstIterator>

The QHash::const_iterator class provides an STL-style const iterator for QHash and QMultiHash.

Calls C++ function: [constructor] void QHash<QString, QVariant>::const_iterator::const_iterator(const QHash<QString, QVariant>::const_iterator& other).

C++ documentation:

The QHash::const_iterator class provides an STL-style const iterator for QHash and QMultiHash.

QHash features both STL-style iterators and Java-style iterators. The STL-style iterators are more low-level and more cumbersome to use; on the other hand, they are slightly faster and, for developers who already know STL, have the advantage of familiarity.

QHash<Key, T>::const_iterator allows you to iterate over a QHash (or a QMultiHash). If you want to modify the QHash as you iterate over it, you must use QHash::iterator instead. It is generally good practice to use QHash::const_iterator on a non-const QHash as well, unless you need to change the QHash through the iterator. Const iterators are slightly faster, and can improve code readability.

The default QHash::const_iterator constructor creates an uninitialized iterator. You must initialize it using a QHash function like QHash::constBegin(), QHash::constEnd(), or QHash::find() before you can start iterating. Here's a typical loop that prints all the (key, value) pairs stored in a hash:

QHash<QString, int> hash;
hash.insert(“January”, 1);
hash.insert(“February”, 2);
...
hash.insert(“December”, 12);
QHash<QString, int>::const_iterator i;
for (i = hash.constBegin(); i != hash.constEnd(); ++i)
      cout << i.key() << “: “ << i.value() << endl;

Unlike QMap, which orders its items by key, QHash stores its items in an arbitrary order. The only guarantee is that items that share the same key (because they were inserted using QHash::insertMulti()) will appear consecutively, from the most recently to the least recently inserted value.

Multiple iterators can be used on the same hash. However, be aware that any modification performed directly on the QHash has the potential of dramatically changing the order in which the items are stored in the hash, as they might cause QHash to rehash its internal data structure. If you need to keep iterators over a long period of time, we recommend that you use QMap rather than QHash.

Warning: Iterators on implicitly shared containers do not work exactly like STL-iterators. You should avoid copying a container while iterators are active on that container. For more information, read Implicit sharing iterator problem.

pub unsafe fn struct_deref(&self) -> Ptr<QVariant>

Returns a pointer to the current result.

Calls C++ function: const QVariant* QHash<QString, QVariant>::const_iterator::operator->() const.

C++ documentation:

Returns a pointer to the current result.

pub unsafe fn sub_assign(&self, j: c_int) -> Ref<ConstIterator>

Makes the iterator go back by j items.

Calls C++ function: QHash<QString, QVariant>::const_iterator& QHash<QString, QVariant>::const_iterator::operator-=(int j).

C++ documentation:

Makes the iterator go back by j items.

See also operator+=() and operator-().

pub unsafe fn value(&self) -> Ref<QVariant>

Returns the current value, converted to a QVariant.

Calls C++ function: const QVariant& QHash<QString, QVariant>::const_iterator::value() const.

C++ documentation:

Returns the current value, converted to a QVariant.

Trait Implementations

impl Add<i32> for &ConstIterator

fn add(self, j: c_int) -> CppBox<ConstIterator>

Returns an iterator to the item at j positions forward from this iterator.

Calls C++ function: QHash<QString, QVariant>::const_iterator QHash<QString, QVariant>::const_iterator::operator+(int j) const.

C++ documentation:

Returns an iterator to the item at j positions forward from this iterator.

See also operator-() and operator+=().

type Output = CppBox<ConstIterator>

The resulting type after applying the + operator.

impl CppDeletable for ConstIterator

unsafe fn delete(&self)

The QHash::const_iterator class provides an STL-style const iterator for QHash and QMultiHash.

Calls C++ function: [destructor] void QHash<QString, QVariant>::const_iterator::~const_iterator().

C++ documentation:

The QHash::const_iterator class provides an STL-style const iterator for QHash and QMultiHash.

QHash features both STL-style iterators and Java-style iterators. The STL-style iterators are more low-level and more cumbersome to use; on the other hand, they are slightly faster and, for developers who already know STL, have the advantage of familiarity.

QHash<Key, T>::const_iterator allows you to iterate over a QHash (or a QMultiHash). If you want to modify the QHash as you iterate over it, you must use QHash::iterator instead. It is generally good practice to use QHash::const_iterator on a non-const QHash as well, unless you need to change the QHash through the iterator. Const iterators are slightly faster, and can improve code readability.

The default QHash::const_iterator constructor creates an uninitialized iterator. You must initialize it using a QHash function like QHash::constBegin(), QHash::constEnd(), or QHash::find() before you can start iterating. Here's a typical loop that prints all the (key, value) pairs stored in a hash:

QHash<QString, int> hash;
hash.insert(“January”, 1);
hash.insert(“February”, 2);
...
hash.insert(“December”, 12);
QHash<QString, int>::const_iterator i;
for (i = hash.constBegin(); i != hash.constEnd(); ++i)
      cout << i.key() << “: “ << i.value() << endl;

Unlike QMap, which orders its items by key, QHash stores its items in an arbitrary order. The only guarantee is that items that share the same key (because they were inserted using QHash::insertMulti()) will appear consecutively, from the most recently to the least recently inserted value.

Multiple iterators can be used on the same hash. However, be aware that any modification performed directly on the QHash has the potential of dramatically changing the order in which the items are stored in the hash, as they might cause QHash to rehash its internal data structure. If you need to keep iterators over a long period of time, we recommend that you use QMap rather than QHash.

Warning: Iterators on implicitly shared containers do not work exactly like STL-iterators. You should avoid copying a container while iterators are active on that container. For more information, read Implicit sharing iterator problem.

impl Decrement for ConstIterator

unsafe fn dec(&self) -> Ref<ConstIterator>

The prefix -- operator (--it) makes the preceding item current and returns an iterator to the new current item.

Calls C++ function: QHash<QString, QVariant>::const_iterator& QHash<QString, QVariant>::const_iterator::operator--().

C++ documentation:

The prefix – operator (–it) makes the preceding item current and returns an iterator to the new current item.

Calling this function on QAssociativeIterable::begin() leads to undefined results.

See also operator++().

type Output = Ref<ConstIterator>

Output type.

impl Increment for ConstIterator

unsafe fn inc(&self) -> Ref<ConstIterator>

The prefix ++ operator (++it) advances the iterator to the next item in the container and returns an iterator to the new current item.

Calls C++ function: QHash<QString, QVariant>::const_iterator& QHash<QString, QVariant>::const_iterator::operator++().

C++ documentation:

The prefix ++ operator (++it) advances the iterator to the next item in the container and returns an iterator to the new current item.

Calling this function on QAssociativeIterable::end() leads to undefined results.

See also operator--().

type Output = Ref<ConstIterator>

Output type.

impl Indirection for ConstIterator

unsafe fn indirection(&self) -> Ref<QVariant>

Returns the current value, converted to a QVariant.

Calls C++ function: const QVariant& QHash<QString, QVariant>::const_iterator::operator*() const.

C++ documentation:

Returns the current value, converted to a QVariant.

type Output = Ref<QVariant>

Output type.

impl PartialEq<Ref<ConstIterator>> for ConstIterator

fn eq(&self, o: &Ref<ConstIterator>) -> bool

Returns true if other points to the same item as this iterator; otherwise returns false.

Calls C++ function: bool QHash<QString, QVariant>::const_iterator::operator==(const QHash<QString, QVariant>::const_iterator& o) const.

C++ documentation:

Returns true if other points to the same item as this iterator; otherwise returns false.

See also operator!=().

fn ne(&self, other: &Rhs) -> bool

This method tests for !=. The default implementation is almost always sufficient, and should not be overridden without very good reason.

impl Sub<i32> for &ConstIterator

fn sub(self, j: c_int) -> CppBox<ConstIterator>

Returns an iterator to the item at j positions backward from this iterator.

Calls C++ function: QHash<QString, QVariant>::const_iterator QHash<QString, QVariant>::const_iterator::operator-(int j) const.

C++ documentation:

Returns an iterator to the item at j positions backward from this iterator.

See also operator+() and operator-=().

type Output = CppBox<ConstIterator>

The resulting type after applying the - operator.