"

 COPYRIGHT (c) 1993 by Claus Gittinger

	      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' }"

OrderedCollection subclass:#SortedCollection

	instanceVariableNames:'sortBlock'

	classVariableNames:'DefaultSortBlock'

	poolDictionaries:''

	category:'Collections-Sequenceable'

!

!SortedCollection class methodsFor:'documentation'!

copyright

"

 COPYRIGHT (c) 1993 by Claus Gittinger

	      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

"

    I keep my elements sorted. The sort order is defined by a sortblock,

    element given as second arg.

    Equal elements may occur multiple times.

    SortedCollection uses quickSort to resort and a binary search when adding/removing

    Because insertion/removal may require that remaining elements have to

    be shifted within the container, adding many individual elements may be done faster

    by creating a completely new collection from the unsorted elements.

    (see examples)

    Thus a sortBlock of [:a :b | a < b] defines ascending sort-order,

    while [:a :b | a > b] defines descening order.

    The default sortBlock for SortedCollections is the first one.

    Compatibility Warning:

    [author:]

"

!

examples

"

    all en-bloeque instead of individually.

    The reason is that for each individual #add:, the contents has to be

    shifted, to create an empty slot for the new element.

    timing example:

    takes 1365 ms on a P5 (admitted: this is a fast machine ;-)

    In contrast:

    takes 383 ms on the same machine.

    If you already have a big sortedCollection at hand, adding multiple

    items may be better done with #addAll:, which resorts all elements, if

    the number of added items is more than some threshold number.

    However, the break-even point where bulk-adding is faster depends

    on the machine ... (and ST/X version ;-).

"

! !

!SortedCollection class methodsFor:'initialization'!

initialize

    "setup the default sortBlock.

     Use #>, since this is the base method in Magnitude."

    "/ only do this once at early startup

    DefaultSortBlock isNil ifTrue:[

    ]

    "

     SortedCollection initialize

    "

    "Modified: 12.4.1996 / 12:29:27 / cg"

! !

!SortedCollection class methodsFor:'instance creation'!

forStrings

    "this is supposed to return a sortedCollection, which sorts using

     the current locales collating sequence. For now, simply use a

     normal string compare.

     This will change"

    ^ self new

    "Modified: 13.9.1997 / 10:18:58 / cg"

    "Created: 13.9.1997 / 10:41:54 / cg"

!

forStrings:size

    "this is supposed to return a sortedCollection, which sorts using

     the current locales collating sequence. For now, simply use a

     normal string compare.

     This will change"

    ^ self new:size

    "Modified: 13.9.1997 / 10:18:58 / cg"

!

new

    "return a new sortedCollection, the sorting is done using

     a compare for a < b, in ascending order"

    ^ super new setSortBlock:DefaultSortBlock

    "Modified: 12.4.1996 / 12:28:18 / cg"

!

new:size

    "return a new sortedCollection with preallocated size.

     The sorting is done using a compare for a < b, in ascending order"

    ^ (super new:size) setSortBlock:DefaultSortBlock

    "Modified: 12.4.1996 / 12:28:22 / cg"

!

sortBlock:aBlock

    "return a new sortedCollection, whe the sort order is defined

     This must be a two-argument block which returns true if its arg1 has to come before

     its arg2 in the collection."

    ^ super new setSortBlock:aBlock

    "default:

     |s|

     s := SortedCollection new.

     s add:15; add:99; add:3; add:-29; add:17; add:-6.

     Transcript showCR:s

    "

    "sorting by absolute values:

     |s|

     s := SortedCollection sortBlock:[:a :b | a abs < b abs].

     s add:15; add:99; add:3; add:29; add:17; add:-6.

     Transcript showCR:s

    "

    "default again:

     |s|

     s := SortedCollection new.

     s add:'foo'; add:'Bar'; add:'baz'; add:'hello'; add:'world'; add:'Wow'.

     Transcript showCR:s

    "

    "sorting strings caseless:

     |s|

     s := SortedCollection sortBlock:[:a :b | a asLowercase < b asLowercase].

     s add:'foo'; add:'Bar'; add:'baz'; add:'hello'; add:'world'; add:'Wow'.

     Transcript showCR:s

    "

    "Modified: 12.4.1996 / 12:26:28 / cg"

!

withAll:aCollection sortBlock:aBlock

    "initialize from aCollection and set the sort-block"

    ^ (self sortBlock:aBlock) addAll:aCollection; yourself

    "

     SortedCollection withAll:#(1 2 3 4 5 6 7 8 9 0)

    "

    "default:

     |s|

     s := SortedCollection withAll:#(15 99 3 29 17 -6).

     Transcript showCR:s

    "

    "sorting by absolute values:

     |s|

     s := SortedCollection withAll:#(15 99 3 29 17 -6) sortBlock:[:a :b | a abs < b abs].

     Transcript showCR:s

    "

    "default again:

     |s|

     s := SortedCollection withAll:#('foo' 'Bar' 'baz' 'hello' 'world' 'Wow').

     Transcript showCR:s

    "

    "sorting strings caseless:

     |s|

     s := SortedCollection withAll:#('foo' 'Bar' 'baz' 'hello' 'world' 'Wow') sortBlock:[:a :b | a asLowercase < b asLowercase].

     Transcript showCR:s

    "

    "Modified: 12.4.1996 / 12:28:09 / cg"

! !

!SortedCollection class methodsFor:'Compatibility-Dolphin'!

sortBlock:aBlock withAll:aCollection

    ^ self withAll:aCollection sortBlock:aBlock

! !

!SortedCollection methodsFor:'adding & removing'!

add:anObject

    "add the argument, anObject at the proper place in the

     receiver. Returns the argument, anObject."

    |index|

    lastIndex < firstIndex "i.e. self size == 0" ifTrue:[

    ] ifFalse:[

    ].

    contentsArray basicAt:index put:anObject.

    ^ anObject

    "

    "

    "Modified: / 13.3.1998 / 16:21:52 / cg"

!

addAll:aCollection

     Returns the argument, aCollection (sigh)."

    |addedCollection|

    (aCollection isSortedCollection

     and:[aCollection sortBlock == sortBlock]) ifTrue:[

    ] ifFalse:[

    ].

    "/

    "/ do a mergeSort with the sortedContents

    "/

    self mergeSorted:addedCollection.

    ^ aCollection

    "

     ( #(7 3 9 10 99) asSortedCollection:[:a :b | a > b])

    "

    "Modified: 13.4.1996 / 12:42:15 / cg"

!

mergeSorted:aSortedCollection

    "add all elements of the argument, aSortedCollection to the

     This leads to an error, if the argument is not a sortedCollection.

     Notice, that quicksort degenerates to a veeery slow bubble-like

     sort when a collection of already sorted elements is given to it.

     Therefore, adding chunks is better done by sorting the chunk and merging

     it in, instead of resorting the receiver."

     contentsArray2

     destIndex "{ Class: SmallInteger }"

     n1        "{ Class: SmallInteger }"

     n2        "{ Class: SmallInteger }"

     srcIndex1 "{ Class: SmallInteger }"

     srcIndex2 "{ Class: SmallInteger }"

     last1     "{ Class: SmallInteger }"

     end1Reached end2Reached

     el1 el2 |

    n1 := self size.

    n2 := aSortedCollection size.

    n1 == 0 ifTrue:[

    ].

    n2 == 0 ifTrue:[

    ].

    newContentsArray := Array new:(n1 + n2).

    destIndex := 1.

    (aSortedCollection isSortedBy:sortBlock) ifTrue:[

    ] ifFalse:[

    ].

    last2 := srcIndex2 + n2 -1.

    srcIndex1 := firstIndex.

    last1 := srcIndex1 + n1 -1.

    (srcIndex1 <= last1 and:[srcIndex2 <= last2]) ifTrue:[

    ].

    "/ fill up with remaining elements from source1

    (srcIndex1 <= last1) ifTrue:[

    ].

    "/ fill up with remaining elements from source2

    (srcIndex2 <= last2) ifTrue:[

    ].

    firstIndex := 1.

    lastIndex := n1 + n2.

    contentsArray := newContentsArray

    "

    "

    "Modified: / 30.1.1998 / 01:49:42 / cg"

! !

!SortedCollection methodsFor:'blocked'!

add:newObject after:oldObject

    "catch this - its not allowed for sortedCollections"

    self shouldNotImplement

!

add:newObject before:oldObject

    "catch this - its not allowed for sortedCollections"

    self shouldNotImplement

!

addFirst:anObject

    "catch this - its not allowed for sortedCollections"

    self shouldNotImplement

!

addLast:anObject

    "catch this - its not allowed for sortedCollections"