#[repr(C)]pub struct ConstIterator { /* private fields */ }
Expand description
The QHash::const_iterator class provides an STL-style const iterator for QHash and QMultiHash.
C++ class: QHash<QString, QVariant>::const_iterator
.
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§
source§impl ConstIterator
impl ConstIterator
sourcepub unsafe fn add_assign(&self, j: c_int) -> Ref<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)
.
Advances the iterator by j items.
See also operator-=() and operator+().
sourcepub unsafe fn copy_from(
&self,
other: impl CastInto<Ref<ConstIterator>>
) -> Ref<ConstIterator>
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)
.
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.
sourcepub unsafe fn dec(&self) -> Ref<ConstIterator>
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--()
.
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++().
sourcepub unsafe fn dec_postfix(&self, arg1: c_int) -> CppBox<ConstIterator>
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)
.
This is an overloaded function.
The postfix -- operator (it--
) makes the preceding item current and returns an iterator to the previously current item.
sourcepub unsafe fn inc(&self) -> Ref<ConstIterator>
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++()
.
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--().
sourcepub unsafe fn inc_postfix(&self, arg1: c_int) -> CppBox<ConstIterator>
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)
.
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.
sourcepub unsafe fn indirection(&self) -> Ref<QVariant>
pub unsafe fn indirection(&self) -> Ref<QVariant>
sourcepub unsafe fn key(&self) -> Ref<QString>
pub unsafe fn key(&self) -> Ref<QString>
sourcepub unsafe fn new() -> CppBox<ConstIterator>
pub unsafe fn new() -> CppBox<ConstIterator>
Constructs an uninitialized iterator.
Calls C++ function: [constructor] void QHash<QString, QVariant>::const_iterator::const_iterator()
.
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().
sourcepub unsafe fn from_void(node: *mut c_void) -> CppBox<ConstIterator>
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)
.
sourcepub unsafe fn from_iterator(
o: impl CastInto<Ref<Iterator>>
) -> CppBox<ConstIterator>
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)
.
Constructs a copy of other.
sourcepub unsafe fn new_copy(
other: impl CastInto<Ref<ConstIterator>>
) -> CppBox<ConstIterator>
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)
.
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.
sourcepub unsafe fn struct_deref(&self) -> Ptr<QVariant>
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
.
Returns a pointer to the current result.
sourcepub unsafe fn sub_assign(&self, j: c_int) -> Ref<ConstIterator>
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)
.
Makes the iterator go back by j items.
See also operator+=() and operator-().
Trait Implementations§
source§impl Add<i32> for &ConstIterator
impl Add<i32> for &ConstIterator
source§fn add(self, j: c_int) -> CppBox<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
.
Returns an iterator to the item at j positions forward from this iterator.
See also operator-() and operator+=().
§type Output = CppBox<ConstIterator>
type Output = CppBox<ConstIterator>
+
operator.source§impl CppDeletable for ConstIterator
impl CppDeletable for ConstIterator
source§unsafe fn delete(&self)
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()
.
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.
source§impl Decrement for ConstIterator
impl Decrement for ConstIterator
source§unsafe fn dec(&self) -> Ref<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--()
.
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>
type Output = Ref<ConstIterator>
source§impl Increment for ConstIterator
impl Increment for ConstIterator
source§unsafe fn inc(&self) -> Ref<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++()
.
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>
type Output = Ref<ConstIterator>
source§impl Indirection for ConstIterator
impl Indirection for ConstIterator
source§impl PartialEq<Ref<ConstIterator>> for ConstIterator
impl PartialEq<Ref<ConstIterator>> for ConstIterator
source§fn eq(&self, o: &Ref<ConstIterator>) -> bool
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
.
Returns true
if other points to the same item as this iterator; otherwise returns false
.
See also operator!=().
source§impl Sub<i32> for &ConstIterator
impl Sub<i32> for &ConstIterator
source§fn sub(self, j: c_int) -> CppBox<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
.
Returns an iterator to the item at j positions backward from this iterator.
See also operator+() and operator-=().
§type Output = CppBox<ConstIterator>
type Output = CppBox<ConstIterator>
-
operator.