"

 COPYRIGHT (c) 2011 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:libbasic2' }"

"{ NameSpace: Smalltalk }"

Collection subclass:#CharacterSet

	instanceVariableNames:'bits'

	classVariableNames:''

	poolDictionaries:''

	category:'Collections-Unordered'

!

!CharacterSet class methodsFor:'documentation'!

copyright

"

 COPYRIGHT (c) 2011 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

"

    Used to represent 8-bit character sets (for now) as a bitmap.

    Bit[n] is set, if Character codePoint:(n-1) is included in the set.

    [author:]

        Claus Gittinger

"

! !

!CharacterSet class methodsFor:'instance creation'!

allSingleByteCharacters

    "return a new character set, which contains all single-byte characters"

    ^ self new addAllSingleByteCharacters

!

empty

    "return a new, empty character set"

    ^ self new

!

new

    "return a new, empty character set"

    ^ self basicNew initialize

    "Created: / 28-01-2011 / 17:29:24 / cg"

!

nonSeparators

    "return a new character set, which contains any but whitespace characters"

    ^ self new 

        addAllSingleByteCharacters;

        removeAll:(Character separators); 

        yourself

!

separators

    "return a new character set, which contains all whitespace characters"

    ^ self new 

        addAll:(Character separators); 

        yourself

! !

!CharacterSet methodsFor:'accessing'!

byteArrayMap

    ^bits

! !

!CharacterSet methodsFor:'adding & removing'!

add:aCharacter

    "add aCharacter to the collection.

     Returns aCharacter (sigh)"

    |cp byteIndex bitIndex|

    cp := aCharacter codePoint.

    self assert:(cp <= 255).

    byteIndex := (cp // 8) + 1.

    bitIndex := (cp \\ 8) + 1.

    byteIndex > bits size ifTrue:[

        bits := (ByteArray new:byteIndex) replaceFrom:1 with:bits.

    ].

    bits at:byteIndex put:((bits at:byteIndex) setBit:bitIndex).

    ^ aCharacter "/ sigh

    "Created: / 28-01-2011 / 17:44:21 / cg"

!

remove:aCharacter ifAbsent:exceptionValue

    |cp byteIndex bitIndex mask|

    cp := aCharacter codePoint.

    self assert:(cp <= 255).

    byteIndex := (cp // 8) + 1.

    bitIndex := (cp \\ 8) + 1.

    byteIndex <= bits size ifTrue:[

        ((mask := bits at:byteIndex) isBitSet:bitIndex) ifTrue:[

            bits at:byteIndex put:(mask clearBit:bitIndex).

            ^ aCharacter

        ].

    ].

    ^ exceptionValue value

    "Created: / 28-01-2011 / 17:51:22 / cg"

! !

!CharacterSet methodsFor:'comparing'!

= something

    ^ (self species = something species)

    and:[ bits = something byteArrayMap ]

!

hash

    ^ bits hash

! !

!CharacterSet methodsFor:'copying-private'!

postCopy

    "make sure that the bitmap is not shared with the copy"

    bits := bits copy

! !

!CharacterSet methodsFor:'initialization'!

addAllSingleByteCharacters

    bits := ByteArray new:"(256 / 8)"32 withAll:16rFF.

    "

     self assert:(

        CharacterSet new addAllCharacters

            includesAll:((Character value:0) to:(Character value:255)))

     self assert:(

        CharacterSet allCharacters

            includesAll:((Character value:0) to:(Character value:255)))

    "

!

initialize

    bits := nil "/ empty

    "Created: / 28-01-2011 / 17:29:48 / cg"

!

setByteArrayMap:aByteArray

    bits := aByteArray

! !

!CharacterSet methodsFor:'queries'!

do:aBlock

    |cp|

    cp := 0.

    bits notNil ifTrue:[

        bits do:[:eachByte |

            eachByte ~~ 0 ifTrue:[

                #(1 2 4 8 16 32 64 128) do:[:mask |

                    (eachByte bitTest:mask) ifTrue:[

                        aBlock value:(Character codePoint:cp).

                    ].

                    cp := cp + 1.

                ].

            ] ifFalse:[

                cp := cp + 8.

            ].

        ]

    ].

    "Created: / 28-01-2011 / 17:39:16 / cg"

!

includes:aCharacter

    "Return true if the set contains aCharacter"

    |cp byteIndex bitIndex|

    cp := aCharacter codePoint.

    (cp > 255) ifTrue:[^ false].

    byteIndex := (cp // 8) + 1.

    bitIndex := (cp \\ 8) + 1.

    byteIndex > bits size ifTrue:[^ false].

    ^ ((bits at:byteIndex) bitAt:bitIndex) ~~ 0

!

size

    |n|

    bits isNil ifTrue:[^ 0].

    n := 0.

    bits do:[:eachByte |

        n := n + (eachByte bitCount)

    ].

    ^ n

    "Created: / 28-01-2011 / 17:35:21 / cg"

! !

!CharacterSet methodsFor:'set operations'!

complement

    "return a character set containing all characters (from codepoint 0 to 255),

     which are NOT included in the receiver"

    ^ self class allSingleByteCharacters

        removeAll:self;

        yourself

! !

!CharacterSet class methodsFor:'documentation'!

version

    ^ '$Header$'

!

version_CVS

    ^ '$Header$'

! !