RangeMap< K, V, MAP > Class Template Reference

#include <rangemap.h>

Detailed Description

template<typename K, typename V, typename MAP = BurstTrieMapSelector<>>
class maxon::RangeMap< K, V, MAP >

Unlike a normal map, a RangeMap maps whole ranges (of integral values) to values. For each contiguous range having the same value, only a single entry is needed, so a RangeMap will perform much better than a normal map if it is likely that consecutive keys are mapped to the same value.

RangeMap<UInt, String> map;
if (!map.Insert(Range<UInt>(10, 40), "Alice"_s))
  return false;
if (!map.Insert(Range<UInt>(30, 50), "Carol"_s))
  return false;
if (!map.Erase(Range<UInt>(15, 25)))
  return false;

The above example results in a map with three entries: The range 10 ... 14 is mapped to "Alice" as well as the range 26 ... 29, while the range 30 ... 50 is mapped to "Carol".

RangeMap ensures that its ranges don't overlap, and that directly adjacent ranges (with no gap between them) which are mapped to the same value are merged to a single range.

RangeMap supports the usual iterators. They iterate through the map per range.

Template Parameters

K	Type of keys. This must be an integral type.
V	Type of values.
MAP	A map selector template to choose the underlying map implementation to use. This has to be an ordered map. Note that the default is the BurstTrieMap which only allows unsigned integral types.

Classes
class	EntryIteratorBase
class	KeyIteratorBase
class	ValueIteratorBase

Public Types
using	MapType = typename MAP::template Type< K, Tuple< K, V > >
using	Range = maxon::Range< K >
using	ValueType = typename MapType::ValueType
using	MapValue = typename MapType::ValueType
using	Iterator = typename MapType::template IteratorTemplate< false, EntryIteratorBase >
using	ConstIterator = typename MapType::template IteratorTemplate< true, EntryIteratorBase >
using	KeyIterator = typename MapType::template IteratorTemplate< false, KeyIteratorBase >
using	ConstKeyIterator = typename MapType::template IteratorTemplate< true, KeyIteratorBase >
using	ValueIterator = typename MapType::template IteratorTemplate< false, ValueIteratorBase >
using	ConstValueIterator = typename MapType::template IteratorTemplate< true, ValueIteratorBase >

Public Member Functions
	RangeMap ()
	RangeMap (RangeMap &&src)
	MAXON_OPERATOR_MOVE_ASSIGNMENT (RangeMap)
Result< void >	CopyFrom (const RangeMap &src)
void	Flush ()
void	Reset ()
Int	GetCount () const
Bool	IsEmpty () const
Bool	IsPopulated () const
Int	GetMemorySize () const
ResultMem	Insert (K rMinValue, K rMaxValue, const V &value)
ResultMem	Insert (K key, const V &value)
ResultMem	Insert (const Range &range, const V &value)
const V *	FindValue (K key) const
const V *	FindRange (K key, Range &rangeOut) const
ResultMem	Erase (K rMinValue, K rMaxValue)
ResultMem	Erase (K key)
ResultMem	Erase (const Range &range)
SFINAEHelper< String, K >::type	ToString (const FormatStatement *fmt=nullptr) const
Iterator	Begin ()
Iterator	End ()
ConstIterator	Begin () const
ConstIterator	End () const
KeyIterator	GetKeys ()
ConstKeyIterator	GetKeys () const
ValueIterator	GetValues ()
ConstValueIterator	GetValues () const
const MapType &	GetMap () const
HashInt	GetHashCode () const
UniqueHash	GetUniqueHashCode () const
Bool	operator== (const RangeMap &other) const
Bool	operator!= (const RangeMap &other) const
const MapType &	GetUnderlyingMap () const

Static Public Member Functions
static Result< void >	DescribeIO (const DataSerializeInterface &stream)

Private Member Functions
	MAXON_DISALLOW_COPY_AND_ASSIGN (RangeMap)

Private Attributes
MapType	_map

Member Typedef Documentation

MapType

using MapType = typename MAP::template Type<K, Tuple<K, V> >

Range

using Range = maxon::Range<K>

ValueType

using ValueType = typename MapType::ValueType

MapValue

using MapValue = typename MapType::ValueType

Iterator

using Iterator = typename MapType::template IteratorTemplate<false, EntryIteratorBase>

ConstIterator

using ConstIterator = typename MapType::template IteratorTemplate<true, EntryIteratorBase>

KeyIterator

using KeyIterator = typename MapType::template IteratorTemplate<false, KeyIteratorBase>

ConstKeyIterator

using ConstKeyIterator = typename MapType::template IteratorTemplate<true, KeyIteratorBase>

ValueIterator

using ValueIterator = typename MapType::template IteratorTemplate<false, ValueIteratorBase>

ConstValueIterator

using ConstValueIterator = typename MapType::template IteratorTemplate<true, ValueIteratorBase>

Constructor & Destructor Documentation

RangeMap() [1/2]

RangeMap

(

)

RangeMap() [2/2]

RangeMap

(

RangeMap< K, V, MAP > &&

src

)

Member Function Documentation

MAXON_OPERATOR_MOVE_ASSIGNMENT()

MAXON_OPERATOR_MOVE_ASSIGNMENT

(

RangeMap< K, V, MAP >

)

CopyFrom()

Result<void> CopyFrom

(

const RangeMap< K, V, MAP > &

src

)

Makes this map a copy of src.

Parameters

[in]

src

Source from which the entries are taken.

Returns

True if copying succeeded.

Flush()

void Flush

(

void

)

Flushes the map. This removes all entries. Depending on the underlying map, memory may still be held for later re-use.

See also

Reset()

Reset()

void Reset

(

void

)

Resets the map. This removes all entries and frees any memory held by the map, so the map will be in a state as if it had been newly constructed.

See also

Flush()

GetCount()

Int GetCount

(

void

)

const

Returns the number of entries in this map. Each contiguous key range where the keys are mapped to the same value requires a single entry.

Returns

Number of entries.

IsEmpty()

Bool IsEmpty

(

)

const

Checks if the RangeMap is empty. This is the same as GetCount() == 0

Returns

True if this RangeMap does not contain any elements.

IsPopulated()

Bool IsPopulated

(

void

)

const

Checks if the RangeMap is populated. This is the same as GetCount() != 0

Returns

True if this RangeMap contains any elements.

GetMemorySize()

Int GetMemorySize

(

void

)

const

Calculates the memory usage for this map. Keys and Values must have a public member GetMemorySize that return the element size.

Returns

Memory size in bytes.

Insert() [1/3]

ResultMem Insert	(	K	rMinValue,
		K	rMaxValue,
		const V &	value
	)

Maps the range rMinValue ... rMaxValue to value. Existing overlapping mappings are truncated, split or removed as necessary, or they are merged with the new mapping if their values are equal. If the range is empty (rMaxValue is less than rMinValue), nothing happens.

Parameters

[in]	rMinValue	Lower boundary of the range.
[in]	rMaxValue	Upper boundary of the range.
[in]	value	Value to which the range shall be mapped.

Returns

False if a memory allocation failed.

Insert() [2/3]

ResultMem Insert	(	K	key,
		const V &	value
	)

Maps the single value key (i.e., the range key ... key consisting of a single element) to value. Existing mappings which overlap key are truncated, split or removed as necessary, or they may be extended to include key if their values are equal.

Parameters

[in]	key	A single key which shall be mapped.
[in]	value	Value to which the range shall be mapped.

Returns

False if a memory allocation failed.

Insert() [3/3]

ResultMem Insert	(	const Range &	range,
		const V &	value
	)

Maps the given range to value. Existing overlapping mappings are truncated, split or removed as necessary, or they are merged with the new mapping if their values are equal. If the range is empty, nothing happens.

Parameters

[in]	range	Range which shall be mapped.
[in]	value	Value to which the range shall be mapped.

Returns

False if a memory allocation failed.

FindValue()

const V* FindValue

(

K

key

)

const

Finds the value associated with the given key in this map. If there is a mapping for a range which contains key, the value of this mapping is returned, otherwise nullptr.

Parameters

[in]

key

Key to search for.

Returns

Pointer to value for the given key, or nullptr if no entry exists for the key.

FindRange()

const V* FindRange	(	K	key,
		Range &	rangeOut
	)		const

Finds the value associated with the given key in this map. If there is a mapping for a range which contains key, rangeOut is set to the range, and the value of the mapping is returned, otherwise nullptr.

Parameters

[in]	key	Key to search for.
[out]	rangeOut	If a mapping is found, rangeOut is set to its range.

Returns

Pointer to value for the given key, or nullptr if no entry exists for the key.

Erase() [1/3]

ResultMem Erase	(	K	rMinValue,
		K	rMaxValue
	)

Removes any mappings of values within the range rMinValue ... rMaxValue. Existing overlapping mappings are truncated, split or removed as necessary.

Parameters

[in]	rMinValue	Lower boundary of the range.
[in]	rMaxValue	Upper boundary of the range.

Returns

False if a memory allocation failed.

Erase() [2/3]

ResultMem Erase

(

K

key

)

Removes a mapping for the given key, if any. Existing overlapping mappings are truncated, split or removed as necessary.

Parameters

[in]

key

Key which shall be unmapped.

Returns

False if a memory allocation failed.

Erase() [3/3]

ResultMem Erase

(

const Range &

range

)

Removes any mappings of values within the given range. Existing overlapping mappings are truncated, split or removed as necessary.

Parameters

[in]

range

Range for which all mappings shall be removed.

Returns

False if a memory allocation failed.

ToString()

SFINAEHelper<String, K>::type ToString

(

const FormatStatement *

fmt = nullptr

)

const

Begin() [1/2]

Iterator Begin

(

)

Returns an iterator pointing to the first entry of this map. The iteration order corresponds to the order of the ranges.

Returns

Iterator for this map pointing to the first element.

End() [1/2]

Iterator End

(

)

Returns an iterator pointing just behind the last entry of this map. The iteration order corresponds to the order of the ranges.

Returns

Iterator for this map pointing behind the last element.

Begin() [2/2]

ConstIterator Begin

(

)

const

Returns an iterator pointing to the first entry of this map. The iteration order corresponds to the order of the ranges.

Returns

Iterator for this map pointing to the first element.

End() [2/2]

ConstIterator End

(

)

const

Returns an iterator pointing just behind the last entry of this map. The iteration order corresponds to the order of the ranges.

Returns

Iterator for this map pointing behind the last element.

GetKeys() [1/2]

KeyIterator GetKeys

(

)

Returns a foreach iterator to iterate over all keys (i.e., ranges) of this map. This will yield all ranges in ascending order.

Returns

Foreach iterator over all keys (i.e., ranges).

GetKeys() [2/2]

ConstKeyIterator GetKeys

(

)

const

Returns a foreach iterator to iterate over all keys (i.e., ranges) of this map. This will yield all ranges in ascending order.

Returns

Foreach iterator over all keys (i.e., ranges).

GetValues() [1/2]

ValueIterator GetValues

(

)

Returns a foreach iterator to iterate over all values of this map. This will yield all values in ascending order of the corresponding ranges.

Returns

Foreach iterator over all values.

GetValues() [2/2]

ConstValueIterator GetValues

(

)

const

Returns a foreach iterator to iterate over all values of this map. This will yield all values in ascending order of the corresponding ranges.

Returns

Foreach iterator over all values.

GetMap()

const MapType& GetMap

(

)

const

GetHashCode()

HashInt GetHashCode

(

)

const

GetUniqueHashCode()

UniqueHash GetUniqueHashCode

(

)

const

operator==()

Bool operator==

(

const RangeMap< K, V, MAP > &

other

)

const

operator!=()

Bool operator!=

(

const RangeMap< K, V, MAP > &

other

)

const

GetUnderlyingMap()

const MapType& GetUnderlyingMap

(

)

const

DescribeIO()

static Result<void> DescribeIO ( const DataSerializeInterface &  stream )

static

MAXON_DISALLOW_COPY_AND_ASSIGN()

MAXON_DISALLOW_COPY_AND_ASSIGN ( RangeMap< K, V, MAP >  )

private

Member Data Documentation

_map

MapType _map

private

The underlying map which maps each start of a range to a pair consisting of the end of the range and the mapped value.