User:Russell.Shackleton/Sandbox

Little_Smalltalk The original version of Little Smalltalk (LST1) was described in the book "A Little Smalltalk", Timothy Budd, Addison-Wesley, ISBN 0-201-10698-1 (ALST). Later versions were written "to be easy to port to new machines and operating systems". Parts of the Little Smalltalk interpreter and the language were modified to achieve this.

Preamble
Little Smalltalk 3.04 DOS (LST3) runs on Microsoft MS-DOS 6.x, Windows 98 and when using the command interpreter (Start > Run > cmd) of Windows NT, 2000 and XP.

The minimum system consists of two files:
 * ST.EXE - the Little Smalltalk interpreter
 * SYSTEMIM - the default Little Smalltalk system image of the standard library

After running ST.EXE, the console displays: Little Smalltalk, Version 3.04

Written by Tim Budd, Oregon State University

object count 2989

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Class Changes
The arrangement of classes and subclasses in the standard library has also changed. LST3 contains 34 classes made up of 435 methods.

Developing Classes
The procedure to add user-defined classes to the standard library described on page 39 ff of ALST has been changed for the DOS environment.


 * 1) Typing editor at the Little Smalltalk prompt returns ms, the name of the default editor. Change this value if you are using a different editor, in most cases this will be Microsoft's editor:
 * > editor <- 'edit.com'
 * 1) Use the addSubClass:instanceVariableNames: method from Class to create your class. For example, to create a HighLow class as a subclass of Object with one instance variable named 'randomnumber':
 * > Object addSubClass: #HighLow instanceVariableNames: 'randomnumber'
 * 1) Use the addSubClass:instanceVariableNames: method from Class to create your class. For example, to create a HighLow class as a subclass of Object with one instance variable named 'randomnumber':
 * > Object addSubClass: #HighLow instanceVariableNames: 'randomnumber'
 * > Object addSubClass: #HighLow instanceVariableNames: 'randomnumber'

Use the following methods of Class to add, edit and view the new methods of the HighLow class:
 * HighLow addMethod - add one method to the class
 * HighLow readMethods - add several methods to the class
 * HighLow editMethod: #methodname - edit the methodname method (note the symbol)
 * HighLow viewMethod: #methodname - view the methodname method

Other Changes
> name <- smalltalk getPrompt: 'name: '
 * LST3 stores the last keyboard input in a one-line history buffer
 * F1 retrieves the next character from the history buffer
 * F3 retrieves the entire history buffer, like the last command in LST1
 * Ins adds the next character typed at the keyboard to the command line
 * Del deletes the next character from the history buffer
 * F6 prints ^Z which is the end-of-file character on the command line. Press Enter to exit from the Little Smalltalk interpreter
 * To return a string in response to a prompt, use the getPrompt: method:

Category:Smalltalk programming language family
 * Be aware of the 8.3 filename restrictions in MS-DOS. Little Smalltalk follows these restrictions in all environments. The EmployeeRecord and EmployeeDatabase classes developed in Chapter 5 of ALST will both be named EMPLOYEE.ST when they are filed out.