gnu-smalltalk-common 3.2.4-2.1 / usr / share / gnu-smalltalk / kernel / UniString.st

"======================================================================
|
|   UnicodeString Method Definitions
|
|
 ======================================================================"

"======================================================================
|
| Copyright 2006, 2009 Free Software Foundation, Inc.
| Written by Paolo Bonzini.
|
| This file is part of the GNU Smalltalk class library.
|
| The GNU Smalltalk class library is free software; you can redistribute it
| and/or modify it under the terms of the GNU Lesser General Public License
| as published by the Free Software Foundation; either version 2.1, or (at
| your option) any later version.
| 
| The GNU Smalltalk class library is distributed in the hope that it will be
| useful, but WITHOUT ANY WARRANTY; without even the implied warranty of
| MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU Lesser
| General Public License for more details.
| 
| You should have received a copy of the GNU Lesser General Public License
| along with the GNU Smalltalk class library; see the file COPYING.LIB.
| If not, write to the Free Software Foundation, 59 Temple Place - Suite
| 330, Boston, MA 02110-1301, USA.  
|
 ======================================================================"



CharacterArray subclass: UnicodeString [
    
    <shape: #utf32>
    <category: 'Collections-Text'>
    <comment: 'My instances represent Unicode string data types.  Data is stored
as 4-byte UTF-32 characters'>

    UnicodeString class >> fromString: aString [
	"Return the String, aString, converted to its Unicode representation.
	 Unless the I18N package is loaded, this is not implemented."

	<category: 'converting'>
	^aString asUnicodeString
    ]

    UnicodeString class >> defaultEncoding [
	"Answer the encoding used by the receiver.  Conventionally, we
	 answer 'Unicode' to ensure that two UnicodeStrings always have
	 the same encoding."

	<category: 'multibyte encodings'>
	^'Unicode'
    ]

    UnicodeString class >> isUnicode [
	"Answer true; the receiver stores characters."

	<category: 'multibyte encodings'>
	^true
    ]

    asString [
	"Returns the string corresponding to the receiver.  Without the
	 Iconv package, unrecognized Unicode characters become $?
	 characters.  When it is loaded, an appropriate single- or
	 multi-byte encoding could be used."

	<category: 'converting'>
	| s each |
	s := String new: self size.
	1 to: self size
	    do: 
		[:i | 
		each := self basicAt: i.
		s at: i
		    put: ((each value between: 0 and: 127) 
			    ifTrue: [each asCharacter]
			    ifFalse: [$?])].
	^s
    ]

    asSymbol [
	"Returns the symbol corresponding to the receiver"

	<category: 'converting'>
	^self asString asSymbol
    ]

    asUnicodeString [
	"But I already am a UnicodeString!  Really!"

	<category: 'converting'>
	^self
    ]

    displayOn: aStream [
	"Print a representation of the receiver on aStream"

	<category: 'converting'>
	self do: [:char | char displayOn: aStream]
    ]

    printOn: aStream [
	"Print a representation of the receiver on aStream"

	<category: 'converting'>
	aStream nextPut: $'.
	self do: 
		[:char | 
		char == $' ifTrue: [aStream nextPut: char].
		char displayOn: aStream].
	aStream nextPut: $'
    ]

    at: anIndex ifAbsent: aBlock [
	"Answer the index-th indexed instance variable of the receiver"

	<category: 'built ins'>
	<primitive: VMpr_Object_basicAt>
	^self checkIndexableBounds: anIndex ifAbsent: aBlock
    ]

    encoding [
	"Answer the encoding used by the receiver.  Conventionally, we
	 answer 'Unicode' to ensure that two UnicodeStrings always have
	 the same encoding."

	<category: 'multibyte encodings'>
	^'Unicode'
    ]

    numberOfCharacters [
	"Answer the number of Unicode characters in the receiver.  This is
	 the same as #size for UnicodeString."

	<category: 'multibyte encodings'>
	^self size
    ]

    hash [
	"Answer an hash value for the receiver"

	<category: 'built-ins'>
	<primitive: VMpr_String_hash>
	^0
    ]
]