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Class: Dictionary

Inheritance:

   Object
   |
   +--Collection
      |
      +--Set
         |
         +--Dictionary
            |
            +--CacheDictionary
            |
            +--Comanche::HttpFormDictionary
            |
            +--Dolphin::LookupTable
            |
            +--GetOpt
            |
            +--IdentityDictionary
            |
            +--OrderedDictionary
            |
            +--PluggableDictionary
            |
            +--RBSearchDictionary
            |
            +--ResourcePack
            |
            +--TIFFReader::TIFFMetaData
            |
            +--VAST::LookupTable
            |
            +--WeakValueDictionary
Package:
stx:libbasic
Category:
Collections-Unordered
Version:
rev: 1.181 date: 2019/07/31 21:15:14
user: cg
file: Dictionary.st directory: libbasic
module: stx stc-classLibrary: libbasic
Author:
Claus Gittinger

Description:


a Dictionary is (conceptionally) a set of Associations storing key-value pairs.
(The implementation uses two arrays to store the keys and values separately.)
Searching for an element is done using a hash into the key array.
Another way of looking at a dictionary is as an array that uses
arbitrary access keys (i.e. not just integers as arrays do).

Since the keys are unordered, no internal element order is defined
(i.e. enumerating them may return elements in any order - even changing
 over time).

Many methods for searching and hashing are inherited from Set.

[Instance variables:]

    keyArray        <Array>         (from Set) the keys

    valueArray      <Array>         the values ('valueArray at:index' corresponds
                                    to the value stored under 'keyArray at:index')

Performance hints:
  since the dictionary does not really store associations internally,
  it is less efficient, to store/retrieve associations. The reason is
  that these assocs are created temporarily in some extract methods.
  I.e. 'at:key put:value' is faster than 'add:anAssoc'
  and 'keysAndValuesDo:' is faster than 'associationsDo:' etc.

  If only symbols or smallIntegers are used as keys, use IdentityDictionaries
  for slightly better performance, since both hashing and comparison is faster.

  If you have a rough idea how big the dictionary is going to grow,
  create it using #new: instead of #new. Even if the size given is a
  poor guess (say half of the real size), there is some 20-30% performance
  win to expect, since many resizing operations are avoided when associations
  are added.

Special note:
  in previous versions, nil was not allowed as valid key
  This has been changed; internally, a special nil-key is used,
  which is converted back to nil whenever keys are accessed.

Related information:

    Set,
    IdentityDictionary,
    IdentitySet,
    WeakIdentitySet
    and
    WeakIdentityDictionary

Class protocol:

Compatibility-Squeak
o  newFrom: aCollectionOfAssociations
return a new instance where associations are taken from the argument

usage example(s): 

     Dictionary newFrom:{#foo -> #Foo. #bar -> #Bar}

     Dictionary
        newFrom:(Dictionary withKeysAndValues:#('one' 1 'two' 2 'three' 3 'four' 4))

o  newFromPairs: aCollectionOfAssociations
return a new instance where associations are taken from the argument

usage example(s): 

     Dictionary newFromPairs:{ 1->#(1 2 3) . 'foo' -> 'bar' }

instance creation
o  decodeFromLiteralArray: anArray
create & return a new instance from information encoded in anArray.

o  withAssociations: aCollectionOfAssociations
return a new instance where associations are taken from the argument

usage example(s): 

     Dictionary withAssociations:{ #'one'->1 .
                                   #'two'->2 .
                                   #'three'->3 .
                                   #'four'->4 }

o  withKeyValuePairs: aCollection
return a new instance where keys and values are taken from
elements of aCollection, which are pairs (2-element SeuqenceableCollection) of key and value

usage example(s): 

     Dictionary withKeyValuePairs:#( ('one' 1) ('two' 2) ('three' 3) ('four' 4))
     Dictionary withKeyValuePairs:#( ('one' 1) ('two' 2) ('three' 3) ('four' 4)) asSet

o  withKeys: keyArray andValues: valueArray
return a new instance where keys and values are taken from
the argumentArrays.

usage example(s): 

     Dictionary withKeys:#('one' 'two' 'three' 'four')
               andValues:#(1 2 3 4)

o  withKeys: aCollection valueBlock: aOneArgBlock
return a Dictionary with keys from aCollection's elements,
using aOneArgBlock to generate the values from aCollection's elements.

usage example(s): 

     Dictionary withKeys:#(10 20 30 40 50 60 70 80 90) valueBlock:[:e| e asString]

o  withKeysAndValues: aSequenceableCollection
return a new instance where keys and values are taken from alternating
elements of aSequenceableCollection

usage example(s): 

     Dictionary withKeysAndValues:#('one' 1 'two' 2 'three' 3 'four' 4)
     Dictionary withKeysAndValues:#('one' 1 'two' 2 'three' 3 'incomplete')

o  withValues: aCollection keyBlock: aOneArgBlock
return a Dictionary with values from aCollection's elements,
using aOneArgBlock to generate the keys from aCollection's elements.

usage example(s): 

     Dictionary withValues:#(10 20 30 40 50 60 70 80 90) keyBlock:[:e| e asString]

Instance protocol:

Compatibility-Dolphin
o  equals: aDictionary

Compatibility-VW5.4
o  contentsEquals: aDictionary
Anwer true if the receiver and aDictionary contain the same key/values.
(ignoring the classes)

Squeak Compatibility
o  hasKeyStartingWith: aString
( an extension from the stx:goodies/webServer/comanche package )

accessing
o  associationAt: aKey
return an association consisting of aKey and the element indexed
by aKey -
report an error, if no element is stored under aKey

o  associationAt: aKey ifAbsent: exceptionBlock
return an association consisting of aKey and the element indexed by aKey -
return result of exceptionBlock if no element is stored under aKey.
Warning: this is a comatibility interface only, with a different semantic as
the original ST80 implementation. The returned assoc is created on the fly,
and not the one stored in the receiver (there are not assocs there)

o  associations
return an ordered collection containing the receiver's associations.

o  at: aKey
return the element indexed by aKey - report an error if none found

o  at: aKey ifAbsent: exceptionBlock
return the element indexed by aKey -
return result of exceptionBlock if no element is stored under aKey

o  at: aKey ifAbsent: default update: aBlock
update the element stored under aKey with the result from
evaluating aBlock with the previous stored value as argument, or with default,
if there was no such key initially.
I.e. this is the same as self at:aKey put:(aBlock value:(self at:aKey ifAbsent:default)).
Return the new value stored.
This is an optimized accessor, which only computes the hash value once.

o  at: aKey ifAbsentPut: valueBlock
return the element indexed by aKey if present,
if not present, store the result of evaluating valueBlock
under aKey and return it.
WARNING: do not add elements while iterating over the receiver.
Iterate over a copy to do this.

o  at: aKey ifPresent: aBlock
try to retrieve the value stored at aKey.
If there is nothing stored under this key, do nothing.
Otherwise, evaluate aBlock, passing the retrieved value as argument.

o  at: aKey ifPresent: presentBlock ifAbsent: absentBlock
try to retrieve the value stored at aKey.
If there is nothing stored under this key,
return the value from absentBlock;
otherwise, answer the value from presentBlock, optionally passing the stored value.

o  at: aKey put: anObject
add the argument anObject under key, aKey to the receiver.
Return anObject (sigh).
WARNING: do not add elements while iterating over the receiver.
Iterate over a copy to do this.

o  at: aKey put: anObject ifPresent: aBlock
if the receiver contains an element stored under aKey,
retrieve it and evaluate aBlock passing the element as argument,
return the block's value.
If not, store aValue under the key.
Use this with an error-reporting block, to ensure that no keys are reused

o  at: aKey update: aBlock
update the element stored under aKey with the result from
evaluating aBlock with the previous stored value as argument.
Report an error if there was no such key initially.
I.e. this is the same as self at:aKey put:(aBlock value:(self at:aKey)).
Return the new value stored.
This is an optimized accessor, which only computes the hash value once.

o  keyAtEqualValue: aValue
return the key whose value is equal (i.e. using #= for compare)
to the argument, nil if none found.
This is a slow access, since there is no fast reverse mapping.
NOTICE:
The value is searched using equality compare;
use #keyAtValue: to compare for identity.

o  keyAtEqualValue: aValue ifAbsent: exceptionBlock
return the key whose value is equal (i.e. using #= for compare)
to the argument, if not found, return the value of exceptionBlock.
This is a slow access, since there is no fast reverse mapping.
NOTICE:
The value is searched using equality compare;
use #keyAtValue:ifAbsent: to compare for identity.

o  keyAtIdenticalValue: aValue
for protocol compatibility only:
return the key whose value is identical (i.e. using #== for compare)
to the argument, nil if none found.
This is a slow access, since there is no fast reverse mapping.
NOTICE:
The value is searched using identity compare;
use #keyAtEqualValue: to compare for equality.

o  keyAtIdenticalValue: aValue ifAbsent: exceptionBlock
for protocol compatibility only:
return the key whose value is identical (i.e. using #== for compare)
to the argument, nil if none found.
This is a slow access, since there is no fast reverse mapping.
NOTICE:
The value is searched using identity compare;
use #keyAtEqualValue: to compare for equality.

o  keyAtIdentityValue: aValue
return the key whose value is identical (i.e. using #== for compare)
to the argument, nil if none found.
This is a slow access, since there is no fast reverse mapping.
NOTICE:
The value is searched using identity compare;
use #keyAtEqualValue: to compare for equality.

o  keyAtIdentityValue: aValue ifAbsent: exceptionBlock
return the key whose value is identical (i.e. using #== for compare)
to the argument, if not found, return the value of exceptionBlock.
This is a slow access, since there is no fast reverse mapping.
NOTICE:
The value is searched using identity compare;
use #keyAtEqualValue:ifAbsent: to compare for equality.

o  keyAtValue: aValue
return the key whose value is identical (i.e. using #== for compare)
to the argument, nil if none found.
This is a slow access, since there is no fast reverse mapping.
NOTICE:
The value is searched using identity compare;
use #keyAtEqualValue: to compare for equality.

o  keyAtValue: aValue ifAbsent: exceptionBlock
return the key whose value is identical (i.e. using #== for compare)
to the argument, if not found, return the value of exceptionBlock.
This is a slow access, since there is no fast reverse mapping
(receiver is searched sequentially).
NOTICE:
The value is searched using identity compare;
use #keyAtEqualValue:ifAbsent: to compare for equality.

o  keys
return a collection containing all keys of the receiver

o  newAt: key put: value
For compatibility with SmallDictionaryWithNElements.
Same operation as at:put:,
with the possibiliy of returning a new instance if there was a need to grow

adding & removing
o  add: anAssociation
add the argument, anAssociation to the receiver.
Returns the argument, anAssociation.

WARNING: do not add elements while iterating over the receiver.
Iterate over a copy to do this.

o  addAll: aCollection
ANSI 5.7.2.1:
Message: addAll: dictionary
Synopsis
Store the elements of dictionary in the receiver at the
corresponding keys from dictionary.
Definition: <abstractDictionary>
This message is equivalent to repeatedly sending the #at:put:
message to the receiver with each of the keys and elements in
dictionary in turn. If a key in dictionary is key equivalent
to a key in the receiver, the associated element in dictionary
replaces the element in the receiver.

Returns the argument, aCollection (sigh).

WARNING: do not add elements while iterating over the receiver.
Iterate over a copy to do this.

o  addOrReplace: anAssociation
add the argument, anAssociation to the receiver.
Returns the argument, anAssociation.

WARNING: do not add elements while iterating over the receiver.
Iterate over a copy to do this.

usage example(s): 

        self new
            add:(1 -> 'one');
            addOrReplace:(1.0 -> 'ONE')   ; yourself

o  addPairsFrom: aSequenceableCollection
merge consecutive key-value pairs from aSequenceableCollection into the receiver.

o  clearContents
remove all elements from the receiver, but do not resize.
Returns the receiver.
Similar to removeAll, but might behave better,
if the receiver is to be filled again afterwards.

o  declare: key from: aDictionary
if the receiver does not include an association for key,
take the association from aDictionary and add it to the receiver.
If aDictionary does not contain such an association, use nil
as the value of the new dictionary.

Stubidity Notice:
Incompatibility with #declareAllFrom:, where the other values are
defined unconditionally.

WARNING: do not add elements while iterating over the receiver.
Iterate over a copy to do this.

o  declareAll: keys from: aCollectionOrDictionary
declare all keys in the first argument, keys
from values taken from the second argument, aCollectionOrDictionary.
If aCollectionOrDictionary is a dictionary, access via the key;
if it is a sequencable collection, add corresponding values pairwise.
Values present in the arg will always end up in the receiver;
i.e. a value coming from the argument is already in the receiver,
the value from aDictionaryOrNil is stored into the receiver.

o  declareAllFrom: aDictionaryOrNil
merge all key-value pairs from aDictionary into the receiver.
Values present in the arg will always end up in the receiver;
i.e. a value coming from the argument is already in the receiver,
the value from aDictionaryOrNil is stored into the receiver.

sigh:
For compatibility with #declare:from: the behavior should be changed as following:
If the receiver already contains a key, the existing value is retained.
To keep the compatibility with other smalltalks, the semantics of this remains
as is, and #declareAllNewFrom: was added for convenience.
See #declareAllNewFrom: which does exactly what this name implies.

o  declareAllNewFrom: aDictionaryOrNil
merge all new key-value pairs from aDictionary into the receiver
i.e. If the receiver already contains a key, the existing value is retained.
See also #declareAllFrom:

o  remove: oldObject ifAbsent: aBlock
remove oldObject from the collection and return it.
If it was not in the collection return the value of aBlock.

This is blocked here; you have to use one of
#removeKey:, #saveRemoveKey:, #removeAssociation:,
#removeValue: or #saveRemoveValue:

o  removeAllKeys: aKeyCollection
remove all associations under each key in aKeyCollection from the collection.
If it was not in the collection report an error.

WARNING: do not remove elements while iterating over the receiver.
See #safeRemoveKey: to do this.

o  removeAllKeys: aKeyCollection ifAbsent: aBlock
remove all associations under each key in aKeyCollection from the collection.
If it was not in the collection return the result from evaluating aBlock
(invoked for each missing element).

WARNING: do not remove elements while iterating over the receiver.
See #saveRemoveKey: to do this.

o  removeAssociation: assoc
remove the association from the collection.
If it was not in the collection report an error.
Only the key is used in the passed argument, and a new
association, for the key and the previously stored value is returned.

WARNING: do not remove elements while iterating over the receiver.
See #saveRemoveKey: to do this.

o  removeIdentityValue: aValue ifAbsent: aBlock
remove (first) the association to aValue from the collection,
return the key under which it was stored previously.
If it was not in the collection return result from evaluating aBlock.
The value is searched using identity compare.

Notice, this does a linear search through the values and may
therefore be slow for big dictionaries.

WARNING: do not remove elements while iterating over the receiver.
See #saveRemoveValue: to do this.

o  removeKey: aKey
remove the association under aKey from the collection,
return the value previously stored there.
If it was not in the collection report an error.

WARNING: do not remove elements while iterating over the receiver.
See #saveRemoveKey: to do this.

o  removeKey: aKey ifAbsent: aBlock
remove the association under aKey from the collection,
return the value previously stored there.
If it was not in the collection return the result
from evaluating aBlock.

WARNING: do not remove elements while iterating over the receiver.
See #saveRemoveKey: to do this.

o  removeValue: aValue
remove (first) the association to aValue from the collection,
return the key under which it was stored previously.
If it was not in the collection, report an error.
The value is searched using equality compare here,
but identity compare in the IdentityDictionary subclass.

Notice, this does a linear search through the values and may
therefore be slow for big dictionaries.

WARNING: do not remove elements while iterating over the receiver.
See #saveRemoveValue: to do this.

o  removeValue: aValue ifAbsent: aBlock
remove (first) the association to aValue from the collection,
return the key under which it was stored previously.
If it was not in the collection return result from evaluating aBlock.
The value is searched using equality compare here,
but identity compare in the IdentityDictionary subclass.

Notice, this does a linear search through the values and may
therefore be slow for big dictionaries.

WARNING: do not remove elements while iterating over the receiver.
See #saveRemoveValue: to do this.

o  safeRemoveKey: aKey
remove the association under aKey from the collection.
Return the value previously stored there.
If it was not in the collection return nil.

In contrast to #removeKey:, this does not resize the underlying collection
and therefore does NOT rehash & change the elements order.
Therefore this can be used while enumerating the receiver,
which is not possible if #removeKey: is used.

WARNING: since no resizing is done, the physical amount of memory used
by the container remains the same, although the logical size shrinks.
You may want to manually resize the receiver using #possiblyShrink.

o  safeRemoveValue: aValue
remove the (first) association to aValue from the collection,
return the key under which it was stored previously.
If it was not in the collection return nil.
The value is searched using equality compare here,
but identity compare in the IdentityDictionary subclass.

In contrast to #removeValue:, this does not resize the underlying collection
and therefore does NOT rehash & change the elements order.
Therefore, this can be used while enumerating the receiver,
which is not possible if #removeValue: is used.

WARNING: since no resizing is done, the physical amount of memory used
by the container remains the same, although the logical size shrinks.
You may want to manually resize the receiver using #possiblyShrink.

o  saveRemoveKey: aKey
bad spelling - kept for backward compatibility (2014-06-04)

** This is an obsolete interface - do not use it (it may vanish in future versions) **

o  saveRemoveValue: aValue
bad spelling - kept for backward compatibility (2014-06-04)

** This is an obsolete interface - do not use it (it may vanish in future versions) **

comparing
o  = aCollection
return true, if the argument is a Dictionary containing the same
key-value pairs as I do

converting
o  asDictionary

o  asKeysAndValues
(comment from inherited method)
return a Dictionary with the receiver's associations as key->value pairs
using each element's key as dictionary key and value as dictionary value.

o  asNewDictionary
return myself as a unique new dictionary

o  associationsOrderedBy: aCollectionOfKeys
return an OrderedCollection of my key-value pairs, ordered by the given key list

o  fromLiteralArrayEncoding: encoding
read my values from an encoding.
The encoding is supposed to be of the form:
(Dictionary key1 val1 ... keyN valN)

usage example(s): 

     Dictionary new fromLiteralArrayEncoding:#(Dictionary 'hello' 'world' 1 'foo')

o  literalArrayEncoding
|dict|

dict := Dictionary new.
dict at:1 put:'bla'.
dict at:'fasel' put:#[1 2 3 4].
dict literalArrayEncoding

o  valuesOrderedBy: aCollectionOfKeys
return an OrderedCollection of my values, ordered by the given key list

copying
o  , anotherDictionaryOrAssociation
return a new dictionary containing a merged set of associations.
If anotherDictionaryOrAssociation includes any of the receiver's keys,
the value from anotherDictionaryOrAssociation will be placed into the
returned result.

o  copyWithout: anAssociation
Return a copy of the dictionary that is 1 smaller than the receiver and
does not include the argument, anAssociation
No error is reported, if elementToSkip is not in the collection.

copying-private
o  postCopy
have to copy the valueArray too

enumerating
o  allKeysDo: aBlock
perform the block for all keys in the collection.
Obsolete: use keysDo: for ST-80 compatibility.

** This is an obsolete interface - do not use it (it may vanish in future versions) **

o  associationsCollect: aBlock
for each key-value pair in the receiver, evaluate the argument, aBlock
and return a collection with the results.

See also:
#keysAndValuesCollect: (which passes separate keys & values)
#collect: (which only passes values)

This is much like #keysAndValuesCollect:, but aBlock gets the
key and value as a single association argument.
#keysAndValuesCollect: and is a bit faster therefore (no intermediate objects).

WARNING: do not add/remove elements while iterating over the receiver.
Iterate over a copy to do this.

o  associationsDo: aBlock
perform the block for all associations in the collection.

See also:
#do: (which passes values to its block)
#keysDo: (which passes only keys to its block)
#keysAndValuesDo: (which passes keys&values)

This is much like #keysAndValuesDo:, but aBlock gets the
key and value as a single association argument.
#keysAndValuesDo: and is a bit faster therefore (no intermediate objects).

WARNING: do not add/remove elements while iterating over the receiver.
Iterate over a copy to do this.

o  associationsDo: aBlock separatedBy: sepBlock
perform the block for all associations in the collection.

See also:
#do: (which passes values to its block)
#keysDo: (which passes only keys to its block)
#keysAndValuesDo: (which passes keys&values)

This is much like #keysAndValuesDo:, but aBlock gets the
key and value as a single association argument.
#keysAndValuesDo: and is a bit faster therefore (no intermediate objects).

WARNING: do not add/remove elements while iterating over the receiver.
Iterate over a copy to do this.

o  associationsReverseDo: aBlock
perform the block for all associations in the collection.
Since dictionary does not define any order of its elements,
this is the same as #associationsDo: here.
Provided for protocol compatibility with OrderedDictionary

o  associationsSelect: aBlock
return a new collection with all elements from the receiver, for which
the argument aBlock evaluates to true.
The block gets keys and values as an association argument.

See also: #keysAndValuesSelect: (which is slightly faster),
#select: (which only passes the value)

This is much like #keysAndValuesSelect:, but aBlock gets the
key and value as a single association argument.
#keysAndValuesSelect: and is a bit faster therefore (no intermediate objects).

WARNING: do not add/remove elements while iterating over the receiver.
Iterate over a copy to do this.

o  do: aBlock
perform the block for all values in the collection.

See also:
#associationsDo: (which passes key-value associations)
#keysAndValuesDo: (which passes keys & values separately)
#keysDo: (which passes keys only)

WARNING: do not add/remove elements while iterating over the receiver.
Iterate over a copy to do this.

o  keysAndValuesDo: aTwoArgBlock
evaluate the argument, aBlock for every element in the collection,
passing both key and element as arguments.

See also:
#associationsDo: (which passes keys->value pairs)
#do: (which only passes values)
#keysDo: (which only passes keys)

This is much like #associationsDo:, but aBlock gets the
key and value as two separate arguments.
#associationsDo: is a bit slower.

WARNING: do not add/remove elements while iterating over the receiver.
Iterate over a copy to do this.

o  keysAndValuesSelect: aBlock
return a new collection with all elements from the receiver, for which
the argument aBlock evaluates to true.
The block gets keys and values as separate arguments.

See also:
#associationsSelect: (which passes key-value pairs),
#keysSelect: (which passes key values),
#select: (which only passes the value)

This is much like #associationsSelect:, but aBlock gets the
key and value as two separate arguments.
#associationsSelect: is a bit slower.

WARNING: do not add/remove elements while iterating over the receiver.
Iterate over a copy to do this.

o  keysDo: aBlock
evaluate the argument, aBlock for every key in the collection.

See also:
#associationsDo: (which passes key-value associations)
#keysAndValuesDo: (which passes keys & values separately)
#do: (which passes values only)

WARNING: do not add/remove elements while iterating over the receiver.
Iterate over a copy to do this.

o  keysSelect: aBlock
return a new collection with all elements from the receiver, for which
the argument aBlock evaluates to true.
The block gets the individual keys as its single argument.

See also:
#associationsSelect: (which passes key->value associations),
#keysAndValuesSelect: (which passes key & value args)
#select: (which passes values as arg),

WARNING: do not add/remove elements while iterating over the receiver.
Iterate over a copy to do this.

o  select: aBlock
return a new collection with all elements from the receiver, for which
the argument aBlock evaluates to true.
The block gets the individual values as its single argument.

See also:
#associationsSelect: (which passes key->value associations),
#keysAndValuesSelect: (which passes key & value args)
#keysSelect: (which passes key values),

WARNING: do not add/remove elements while iterating over the receiver.
Iterate over a copy to do this.

o  valuesDo: aBlock
perform the block for all values in the collection.
Same as #do: - for VisualWorks compatibility

o  xor: aCollection
return a new set containing all elements,
which are contained in either the receiver or aCollection, but not in both.

usage example(s): 

     (Dictionary withKeysAndValues:#(1 'uno' 2 'due' 3 'tre' 4 'quatro'))
        xor:(Dictionary withKeysAndValues:#(1 'uno'  4 'quatro' 5 'cinque'))

inspecting
o  inspector2TabLabel
( an extension from the stx:libtool package )
label of the main tab

o  inspectorClass
( an extension from the stx:libtool package )
redefined to use DictionaryInspector
(instead of the default Inspector).

o  inspectorExtraAttributes
( an extension from the stx:libtool package )
(comment from inherited method)
extra (pseudo instvar) entries to be shown in an inspector.
Answers a dictionary of aString -> aBlock.
aString is name of extra attribute and MUST start with minus ($-).
aBlock returns the object representing extra attribute

o  inspectorValueListIconFor: anInspector
( an extension from the stx:libtool package )
returns the icon to be shown alongside the value list of an inspector

printing & storing
o  printElementsDo: aBlock
redefined, so #printOn: prints associations

o  storeOn: aStream
output a printed representation (which can be re-read)
onto the argument aStream

usage example(s): 

     Dictionary new storeOn:Transcript

     (Dictionary new at:1 put:'hello'; yourself) storeOn:Transcript

     (Dictionary new at:1 put:'hello'; at:2 put:nil; yourself) storeOn:Transcript

private
o  compareSame: element1 with: element2
compare two elements for being the same. Here, return true if the
elements are equal (i.e. using #=).
Redefinable in subclasses.

o  emptyCollectionForKeys
return an empty collection to hold keys. Here, a Set is returned.
Redefinable in subclasses.

o  grow: newSize
grow the receiver to make space for at least newSize elements.
To do this, we have to rehash into the new arrays.
(which is done by re-adding all elements to a new, empty key/value array pair).

o  initializeForCapacity: minSize
initialize the contents array (for at least minSize slots)
and set tally to zero.
The size is increased to the next prime for better hashing behavior.

o  possiblyShrinkToZero

o  rehash
rehash contents - is done by re-adding all elements to a new, empty key/value array pair).

o  rehashFrom: startIndex
rehash elements starting at index - after a remove.
NOTE: this method is no longer needed;
the trick using DeletedEntry avoids the need to do this time
consuming operation, making remove pretty fast :-)

o  valueContainerOfSize: n
return a container for values of size n.
Extracted to make life of weak subclasses easier ...

queries
o  includes: anObject
return true, if the argument, aValue is stored in the dictionary,
i.e. if there is an associaten, with aValue as value.
This is a slow search, since there is no fast reverse mapping;
the values have to be all scanned without any hashing.
You need a special collection (or two Dictionaries) to get this
reverse mapping fast.

o  includesAssociation: anAssociation
return true, if there is an association in the receiver with the
same key and value as the argument, anAssociation.
NOTICE: in contrast to #includes:, this compares both key and value.

o  includesEqualValue: aValue
return true, if the argument, aValue is stored in the dictionary,
i.e. if there is an associaten, with aValue as value.
This is a slow search, since there is no fast reverse mapping;
the values have to be all scanned without any hashing.
You need a special collection (or two Dictionaries) to get this
reverse mapping fast.

o  includesIdenticalValue: aValue
return true, if the argument, aValue is stored in the dictionary,
i.e. if there is an associaten, with aValue as value.
This is a slow search, since there is no fast reverse mapping;
the values have to be all scanned without any hashing.
You need a special collection (or two Dictionaries) to get this
reverse mapping fast.

o  includesKey: aKey
return true, if the argument, aKey is a key in the receiver

o  includesValue: aValue
return true, if the argument, aValue is stored in the dictionary,
i.e. if there is an associaten, with aValue as value.
This is a slow search, since there is no fast reverse mapping;
the values have to be all scanned without any hashing.
You need a special collection (or two Dictionaries) to get this
reverse mapping fast.

o  occurrencesOf: anObject
count & return how often anObject is stored in the dictionary.
This counts values - not keys. Uses #= (i.e. equality) compare.

o  speciesForCollecting
like species, but used when doing collect operations.
Redefined for collections which return a different classes object when doing collect.

searching
o  findFirst: aBlock ifNone: exceptionValue
find the index of the first element, for which evaluation of the argument, aBlock returns true;
return its index or the value from exceptionValue if none detected.
This is much like #detect:ifNone:, however, here an INDEX is returned,
while #detect:ifNone: returns the element.

Here we return the first key for which aBlock matches the value.
Note that there is no order in a Dictionary, so any element is first.

usage example(s): 

        (Dictionary withKeys:#('a' 'b' 'c') andValues:#('bla' 'hello' 'hallo'))
            findFirst:[:v| v first = $h].

o  findFirstKey: aBlock
find and return the first key, for which evaluation of the argument, aBlock
returns true; return nil if none is detected.

testing
o  isDictionary
return true, if the receiver is some kind of dictionary;
true returned here - the method is redefined from Object.

visiting
o  acceptVisitor: aVisitor with: aParameter
dispatch for visitor pattern; send #visitDictionary:with: to aVisitor

xml conversion
o  asXMLDocument
( an extension from the stx:goodies/xml/stx package )

o  asXMLElementNamed: aName
( an extension from the stx:goodies/xml/stx package )

Examples:


    |d|

    d := Dictionary new.
    d at:'1' put:'one'.
    d at:2 put:'two'.
    d at:2

    |d|

    d := Dictionary new.
    d at:'1' put:'one'.
    d at:2   put:nil.
    d.
    d at:2

    |d|

    d := Dictionary new.
    d at:'1' put:'one'.
    d at:2   put:nil.
    d includes:nil.

    |d|

    d := Dictionary new.
    d at:'1' put:'one'.
    d includes:nil.

    |d1 d2|

    d1 := Dictionary withKeys:#(a b c) andValues:#( 1 2 3).
    d2 := Dictionary newFrom:d1.
    d2.

ST/X 7.2.0.0; WebServer 1.670 at bd0aa1f87cdd.unknown:8081; Wed, 27 Sep 2023 19:30:57 GMT