- Qt 5.15
- Qt Core
- C++ Classes
- QMutableHashIterator
- Qt 5.15.19 Reference Documentation

# Obsolete Members for QMutableHashIterator

The following members of class QMutableHashIterator are obsolete. They are provided to keep old source code working. We strongly advise against using them in new code.

## Public Functions

`(obsolete)` bool | findPrevious(const T &value)
`(obsolete)` bool | hasPrevious() const
`(obsolete)` Item | peekPrevious() const
`(obsolete)` Item | previous()

## Member Function Documentation

### bool QMutableHashIterator::findPrevious(const T &value)

This function is obsolete. It is provided to keep old source code working. We strongly advise against using it in new code.

Deprecated in order to align with std::unordered_set functionality.

Searches for value starting from the current iterator position backward. Returns `true` if a (key, value) pair with value value is found; otherwise returns `false`.

After the call, if value was found, the iterator is positioned just before the matching item; otherwise, the iterator is positioned at the front of the container.

See also findNext().

### bool QMutableHashIterator::hasPrevious() const

This function is obsolete. It is provided to keep old source code working. We strongly advise against using it in new code.

Deprecated in order to align with std::unordered_set functionality.

Returns `true` if there is at least one item behind the iterator, i.e. the iterator is not at the front of the container; otherwise returns `false`.

See also hasNext() and previous().

### Item QMutableHashIterator::peekPrevious() const

This function is obsolete. It is provided to keep old source code working. We strongly advise against using it in new code.

Deprecated in order to align with std::unordered_set functionality.

Returns the previous item without moving the iterator.

Call key() on the return value to obtain the item's key, and value() to obtain the value.

Calling this function on an iterator located at the front of the container leads to undefined results.

See also hasPrevious(), previous(), and peekNext().

### Item QMutableHashIterator::previous()

This function is obsolete. It is provided to keep old source code working. We strongly advise against using it in new code.

Deprecated in order to align with std::unordered_set functionality.

Returns the previous item and moves the iterator back by one position.

Call key() on the return value to obtain the item's key, and value() to obtain the value.

Calling this function on an iterator located at the front of the container leads to undefined results.

See also hasPrevious(), peekPrevious(), and next().