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Little Smalltalk Dave’s Smalltalk FAQ Copyright (c) 1995 and 1996 by David N. Smith. All Rights Reserved. Email: [email protected] Last-modified: 28 July 1995 Certain questions get asked time and again. In order to save the repeated answering of these questions, and to provide the best answers, collections of these ’frequently asked questions’, and their answers, of course, are made and distributed to interested parties. Called FAQs, these documents often become the basic documentation on a topic and should be checked before posting a question to a related newsgroup. This file is a set of frequently asked questions for the Smalltalk language. There are several such Smalltalk FAQs; this one is by David N. Smith. Thanks to all those on comp.lang.smalltalk who asked questions, answered questions, and provided an inspirational environment in which the seeds of this FAQ grew and propsered. Format and Availability A table of contents to this FAQ is distributed periodically on the newsgroup comp.lang.smalltalk. It consists of a text version of part one of the FAQ. The FAQ itself is available in several formats including Postscript™ and Adobe™ Acrobat™ formats. It is available online at: URL: http://st-www.cs.uiuc.edu/users/dnsmith/SmallFaq.html and URL: http://www.dnsmith.com/SmallFAQ/SmallFaq.html There is no text-only version; not providing one is somewhat unusual, but so is having a typeset FAQ. The fonts used are the ever-present Times and Courier, selected because every postscript printer known to man has them builtin. It is thus Copyright (c) 1996 by David N. Smith. All Rights Reserved. DRAFT 1 not necessary to distribute copies of the fonts in the postscript and Acrobat files.At the moment there is no HTML version; one will appear when suitable and satisfactory methods of translating Adobe FrameMaker files to HTML are available. If you have not already read the overall Usenet introductory material posted to "news.announce.newusers", please do. It is also available by ftp in: URL: ftp://garbo.uwasa.fi/pc/doc-net/usenews.zip Status This is a draft document. It surely contain errors in its statements and bugs in its code. Some obvious questions are not present. Many questions are asked but left unanswered. The obvious questions will be asked and the unanswered questions will be answered in the fullness of time. Chapters nearer the front of the document are more complete than chapters nearer the back. There are many notes from the author to the author: These are usually right aligned and flagged with a triangle.n Craig Latta’s Smalltalk FAQ Another Smalltalk FAQ is by Craig Latta and is available in text format at: URL: ftp://XCF.Berkeley.EDU/pub/misc/smalltalk/FAQ/FAQ.txt or: URL: ftp://rtfm.mit.edu/pub/usenet-by-hierarchy/comp/lang/smalltalk/ and in HTML format at: URL: http://XCF.Berkeley.EDU/pub/misc/smalltalk/FAQ. Vikas Malik’s Smalltalk FAQ Yet another Smalltalk FAQ is by Vikas Malik and is available in HTML format at: URL: http://www.infi.net/~vmalik/ The Object People’s IBM Smalltalk FAQ The Object People maintain a FAQ on IBM Smalltalk at: URL: http://www.objectpeople.on.ca/~wayne/faq/visualage/ 2 DRAFT Copyright (c) 1996 by David N. Smith. All Rights Reserved. IBM’s Smalltalk FAQ IBM maintains a FAQ on IBM Smalltalk at: URL: http://www.torolab.ibm.com/software/ad/vishints.html Trademarks Many trademarks are used in this FAQ. These trademarks are the property of their respective owners. When known to the author, trademarks are indicated by an uppercase leading letter, or a word entirely in uppercase letters as appropriate. Quoted material without other attribution is from an obvious (and referenced) URL. Updates and Corrections Comments from readers are not only welcome but are invited. • Are the questions the right ones? • Are the answers suitable and at the right level? • What topics need to be covered? • What questions should be added? The author does not have access to all existing Smalltalk system (nor the time to be an expert in all the ones he does have). If you have information on specific implementations that should go into any question, please forward it to the author. If you have corrections or suggestions for this FAQ, send them to David N. Smith at [email protected] or [email protected]. Please include: your name, your email address; and your telephone number or snail- mail address. Submission of an update, correction, or additional topic grants permission to use the information in the FAQ and derivitive works if any, unless otherwise stated. Acknowledgement of sources will be limited to the submitters name and email address, unless requested otherwise, and subject to the editors judgement. Thank you. Copyright (c) 1996 by David N. Smith. All Rights Reserved. DRAFT 3 Short Table of Contents General Questions Learning the Smalltalk Language ......................................................................................................2 Conferences......................................................................................................................................11 Smalltalk Places on the Net..............................................................................................................13 Smalltalk Implementations ANSI Smalltalk ................................................................................................................................22 Digitalk Visual Smalltalk.................................................................................................................23 Dolphin Smalltalk ............................................................................................................................24 Enfin Smalltalk.................................................................................................................................24 GemStone Smalltalk.........................................................................................................................25 GNU Smalltalk.................................................................................................................................25 IBM Smalltalk and VisualAge .........................................................................................................26 Little Smalltalk.................................................................................................................................27 Object Connect’s MT Smalltalk.......................................................................................................28 Object Technology International......................................................................................................29 ParcPlace VisualWorks Smalltalk....................................................................................................30 ParcPlace-Digitalk Smalltalk ...........................................................................................................31 QKS SmalltalkAgents ......................................................................................................................32 SELF Smalltalk ................................................................................................................................33 Smalltalk-X ......................................................................................................................................34 VMARK Enfin Smalltalk.................................................................................................................35 Definitions of Terms Definitions of Terms: Objects ..........................................................................................................37 Definitions of Terms: Messages.......................................................................................................40 Definitions of Terms: Classes ..........................................................................................................41 The Smalltalk Language Literals..............................................................................................................................................43 Variables and Names........................................................................................................................50 Global Variables...............................................................................................................................57 Class Variables and Class Instance Variables..................................................................................58 Pool Dictionaries..............................................................................................................................60 Classes..............................................................................................................................................64 What Variables Hold........................................................................................................................68 Blocks...............................................................................................................................................71 Methods............................................................................................................................................78 4 DRAFT Copyright (c) 1996 by David N. Smith. All Rights Reserved. Inheritance, Self and Super ..............................................................................................................81 Objects Object Identity..................................................................................................................................87
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