"
 COPYRIGHT (c) 1998 by eXept Software AG
              All Rights Reserved

 This software is furnished under a license and may be used
 only in accordance with the terms of that license and with the
 inclusion of the above copyright notice.   This software may not
 be provided or otherwise made available to, or used by, any
 other person.  No title to or ownership of the software is
 hereby transferred.
"
"{ Package: 'stx:libbasic' }"

"{ NameSpace: Smalltalk }"

Collection subclass:#KeyedCollection
	instanceVariableNames:''
	classVariableNames:''
	poolDictionaries:''
	category:'Collections-Abstract'
!

!KeyedCollection class methodsFor:'documentation'!

copyright
"
 COPYRIGHT (c) 1998 by eXept Software AG
              All Rights Reserved

 This software is furnished under a license and may be used
 only in accordance with the terms of that license and with the
 inclusion of the above copyright notice.   This software may not
 be provided or otherwise made available to, or used by, any
 other person.  No title to or ownership of the software is
 hereby transferred.
"

!

documentation
"
    Abstract superclass for collections which have a key->value mapping.
    This abstract class provides functionality common to those collections,
    without knowing how the concrete class implements things. 
    Thus, all methods found here depend on some basic mechanisms 
    to be defined in the concrete class. 
    These basic methods are usually defined as #subclassResponsibility here.
    Some methods are also redefined for better performance.

    Subclasses should at least implement:
        at:ifAbsent:        - accessing elements
        removeKey:ifAbsent  - removing
        keysAndValuesDo:    - enumerating

    [author:]
        Claus Gittinger
"
! !

!KeyedCollection class methodsFor:'instance creation'!

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

    |newDict sz "{ Class: SmallInteger }"|

    sz := aCollectionOfAssociations size.
    newDict := self new:sz.
    aCollectionOfAssociations do:[:assoc |
        newDict at:assoc key put:assoc value
    ].
    ^ newDict

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

    "Created: / 16-03-2017 / 12:15:38 / stefan"
!

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

    |newColl sz "{ Class: SmallInteger }"|

    sz := keyArray size.
    newColl := self new:sz.
    1 to:sz do:[:index |
        newColl at:(keyArray at:index) put:(valueArray at:index).
    ].
    ^ newColl

    "Created: / 16-03-2017 / 11:06:51 / stefan"
    "Modified (format): / 16-03-2017 / 12:12:09 / stefan"
!

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

    |newDict sz "{ Class: SmallInteger }"|

    sz := anArray size.
    newDict := self new:(sz // 2).
    1 to:sz by:2 do:[:i |
        newDict at:(anArray at:i) put:(anArray at:i+1)
    ].
    ^ newDict

    "
     KeyValueList withKeysAndValues:#('one' 1 'two' 2 'three' 3 'four' 4)
    "

    "Created: / 16-03-2017 / 12:13:27 / stefan"
! !

!KeyedCollection class methodsFor:'queries'!

isAbstract
    "Return if this class is an abstract class.
     True is returned for KeyedCollection here; false for subclasses.
     Abstract subclasses must redefine this again."

    ^ self == KeyedCollection
! !

!KeyedCollection methodsFor:'accessing'!

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

    ^ self associationAt:aKey ifAbsent:[self errorKeyNotFound:aKey]

    "Modified: / 16-03-2017 / 17:19:52 / stefan"
!

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)"

    |value|

    value := self at:aKey ifAbsent:[^ exceptionBlock value].
    ^ Association key:aKey value:value.

    "Created: / 16-03-2017 / 17:17:05 / stefan"
!

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

    |coll|

    coll := OrderedCollection new.
    self associationsDo:[:assoc | coll add:assoc].
    ^ coll

    "Created: / 16-03-2017 / 17:30:47 / stefan"
!

at:key
    "return the value stored under akey.
     Raise an error if not found"

    ^ self at:key ifAbsent:[self errorKeyNotFound:key].

    "Modified: / 19.6.1998 / 00:48:27 / cg"
!

at:key ifAbsent:exceptionBlock
    "return the value stored under akey.
     Return the value from evaluating exceptionBlock if not found"

    ^ self subclassResponsibility

    "Created: / 19.6.1998 / 00:48:23 / cg"
!

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.
     Return the new value stored."

    ^ self at:aKey put:(aBlock value:(self at:aKey ifAbsent:default))

    "Created: / 16-03-2017 / 17:28:15 / stefan"
!

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."

    ^ self at:aKey ifAbsent:[self at:aKey put:valueBlock value].

    "Created: / 16-03-2017 / 17:23:07 / stefan"
!

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."

    |v|

    v := self at:aKey ifAbsent:[^ nil].
    ^ aBlock value:v.

    "Created: / 16-03-2017 / 17:11:27 / stefan"
!

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."

    ^ self subclassResponsibility

    "Created: / 16-03-2017 / 17:33:12 / stefan"
!

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 blocks value.
     If not, store aValue under the key.
     Use this with an error-reporting block, to ensure that no keys are reused"

    |value isAbsent|

    value := self at:aKey ifAbsent:[isAbsent := true. self at:aKey put:anObject].
    isAbsent notNil ifTrue:[
        ^ value.
    ].

    ^ aBlock value:value.

    "Created: / 16-03-2017 / 17:38:00 / stefan"
!

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.
     Return the new value stored."

    ^ self at:aKey put:(aBlock value:(self at:aKey))

    "Created: / 16-03-2017 / 17:29:22 / stefan"
!

keyAtEqualValue:value
    "return the key under which value is stored.
     Raise an error if not found.
     This is a slow access, since the receiver is searched sequentially.
     NOTICE:
        The value is searched using equality compare"

    ^ self keyAtEqualValue:value ifAbsent:[self errorValueNotFound:value].

    "Created: / 07-02-2017 / 11:11:41 / cg"
!

keyAtEqualValue:value ifAbsent:exceptionBlock
    "return the key under which value is stored.
     If not found, return the value from evaluating exceptionBlock.
     This is a slow access, since the receiver is searched sequentially.
     NOTICE:
        The value is searched using equality compare"

    self keysAndValuesDo:[:elKey :elValue |
        value = elValue ifTrue:[^ elKey]
    ].
    ^ exceptionBlock value

    "Created: / 07-02-2017 / 11:12:03 / cg"
!

keyAtIdenticalValue:value
    "return the key under which value is stored.
     Raise an error if not found.
     This is a slow access, since the receiver is searched sequentially.
     NOTICE:
        The value is searched using identity compare"

    ^ self keyAtIdenticalValue:value ifAbsent:[self errorValueNotFound:value].

    "Created: / 07-02-2017 / 11:12:23 / cg"
!

keyAtIdenticalValue:value ifAbsent:exceptionBlock
    "return the key under which value is stored.
     If not found, return the value from evaluating exceptionBlock.
     This is a slow access, since the receiver is searched sequentially.
     NOTICE:
        The value is searched using identity compare"

    self keysAndValuesDo:[:elKey :elValue |
        value == elValue ifTrue:[^ elKey]
    ].
    ^ exceptionBlock value

    "Created: / 07-02-2017 / 11:12:46 / cg"
!

keyAtValue:value
    "return the key under which value is stored.
     Raise an error if not found.
     This is a slow access, since the receiver is searched sequentially.
     NOTICE:
        The value is searched using equality compare"


    ^ self keyAtEqualValue:value.

    "Created: / 19-06-1998 / 00:49:16 / cg"
    "Modified (comment): / 07-02-2017 / 11:13:29 / cg"
    "Modified (comment): / 16-03-2017 / 18:00:28 / stefan"
!

keyAtValue:value ifAbsent:exceptionBlock
    "return the key under which value is stored.
     If not found, return the value from evaluating exceptionBlock.
     This is a slow access, since the receiver is searched sequentially.
     NOTICE:
        The value is searched using equality compare"


    ^ self keyAtEqualValue:value ifAbsent:exceptionBlock.

    "Created: / 19-06-1998 / 00:50:34 / cg"
    "Modified: / 07-02-2017 / 11:13:20 / cg"
    "Modified (comment): / 16-03-2017 / 18:00:37 / stefan"
!

keys
    "return a collection containing the keys of the receiver"

    |keyCollection|

    keyCollection := OrderedCollection new.
    self keysDo:[:aKey |
        keyCollection add:aKey
    ].
    ^ keyCollection

    "Modified: / 19.6.1998 / 00:48:27 / cg"
    "Created: / 19.6.1998 / 00:51:49 / cg"
! !

!KeyedCollection methodsFor:'enumerating'!

do:aBlock
    "evaluate aBlock for each value"

    self keysAndValuesDo:[:elKey :elValue | aBlock value:elValue]

    "Created: / 19.6.1998 / 00:56:24 / cg"
!

keysAndValuesDo:aBlock
    "evaluate aBlock for each key and value"

    ^ self subclassResponsibility

    "Created: / 19.6.1998 / 00:56:52 / cg"
! !

!KeyedCollection methodsFor:'removing'!

removeKey:aKey
    "remove key (and the value stored under that key) from the
     receiver; raise an error if no such element is contained"

    ^ self removeKey:aKey ifAbsent:[self errorKeyNotFound:aKey]

    "Created: / 19.6.1998 / 00:53:25 / cg"
    "Modified: / 19.6.1998 / 00:54:02 / cg"
!

removeKey:aKey ifAbsent:exceptionBlock
    "remove key (and the value stored under that key) from the
     receiver; return the value which was stored previously there.
     If no such element is contained, return the value
     from evaluating exceptionBlock"

    ^ self subclassResponsibility

    "Created: / 19.6.1998 / 00:53:58 / cg"
! !

!KeyedCollection methodsFor:'searching'!

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."

    self keysAndValuesDo:[:eachKey :eachValue| (aBlock value:eachValue) ifTrue:[^ eachKey]].
    ^ exceptionValue value.

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

    "Created: / 16-03-2017 / 17:46:02 / stefan"
!

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

    self keysDo:[:key |
        (aBlock value:key) ifTrue:[^ key].
    ].
    ^ nil

    "Created: 8.10.1996 / 22:01:31 / cg"
    "Modified: 8.10.1996 / 22:02:03 / cg"
! !

!KeyedCollection methodsFor:'testing'!

includesIdenticalKey:aKey
    "return true, if the argument, aKey is a key in the receiver"

    self keysDo:[:elKey | aKey == elKey ifTrue:[^ true]].
    ^ false

    "Created: / 19.6.1998 / 00:55:05 / cg"
!

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

    self keysDo:[:elKey | aKey = elKey ifTrue:[^ true]].
    ^ false

    "Created: / 19.6.1998 / 00:55:05 / cg"
! !

!KeyedCollection class methodsFor:'documentation'!

version
    ^ '$Header$'
!

version_CVS
    ^ '$Header$'
! !