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Smalltalk Programming Interview Questions and Answers

What Is Smalltalk?
Smalltalk is pure object oriented programming (OOPs), dynamically typed and reflective programming language.

Smalltalk is an improvement environment – class browsers, debugger, inspector and refactoring engine.

Everything is an object –variables, constants, activation records and classes.

Smalltalk was designed and created by Learning Research Group of Xerox PARC in 1972 and the Researcher Team –
ü  Alan Kay
ü  Dan Ingalls
ü  Adele Goldberg
ü  Ted Kaehler
ü  Scott Wallace
ü  And so on
All computation is performed by objects sending and receiving messages – 1+2*3
What Types of characters Allowable in Smalltalk?
ü  0-9
ü  A-Z
ü  a-z
ü  .+/*~<>@%|&?
ü  blank, tab, cr, ff, lf
ü  And so on

How To Declare Variables in Smalltalk?
ü  Variables must be declared before use
ü  Shared variables must begin with uppercase
ü  Local variables must begin with lowercase
ü  Reserved names - true, false, nil, self and super

What Is the Variable scope in Smalltalk?
ü  Global
ü  Class
ü  Class Instance
ü  Pool
ü  Block Temporary
ü  Method Temporary
ü  Method Parameters
ü  Instance Variables

References links
By Anil Singh | Rating of this article (*****)

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