Class: LazyArray

• Inheritance
• Description
• Class protocol
  • initialization
  • instance creation
• Instance protocol
  • accessing
• Private classes
• Examples

Inheritance:

   Object
   |
   +--Collection
      |
      +--SequenceableCollection
         |
         +--ArrayedCollection
            |
            +--LazyArray

Package:

stx:libbasic2

Category:

Collections-Arrayed

Version:

rev: 1.7 date: 2021/01/20 14:02:42

user: cg

file: LazyArray.st directory: libbasic2

module: stx stc-classLibrary: libbasic2

Description:

An Array which computes its values lazily (on demand) and remembers them.
Useful if it is relatively expensive to compute an element, 
and it may be needed again later.

copyright
COPYRIGHT (c) 2003 by Claus Gittinger
             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.

Class protocol:

 initialize

self initialize

 new: size

(comment from inherited method)
return an instance of myself with anInteger indexed variables

Instance protocol:

 at: index

(comment from inherited method)
return the indexed instance variable with index, anInteger;
this method can be redefined in subclasses.

 valueGenerator: aBlock

Private classes:

    UncomputedValue

Examples:

    |squares|

    squares := LazyArray new:100.
    squares valueGenerator:[:index | index squared].

    squares at:50.   
    squares inspect.