Class: SignedWordArray

• Inheritance
• Description
• Class protocol
  • queries

Inheritance:

   Object
   |
   +--Collection
      |
      +--SequenceableCollection
         |
         +--ArrayedCollection
            |
            +--UninterpretedBytes
               |
               +--AbstractNumberVector
                  |
                  +--UnboxedIntegerArray
                     |
                     +--SignedWordArray

Package:

stx:libbasic

Category:

Collections-Arrayed

Version:

rev: 1.12 date: 2022/08/10 10:07:37

user: cg

file: SignedWordArray.st directory: libbasic

module: stx stc-classLibrary: libbasic

Description:

SignedWordArrays store 16bit signed integers in the range 16r-8000..16r7FFF.
They are much like WordArrays, but the values stored are signed.
In contrast to normal arrays (which store pointers to their elements),
signedWordArrays store the values in a dense & compact way. 
Since the representation fits the underlying C-language systems representation
of signed int16's, this is also useful to pass bulk data to c primitive code.

Therefore, SignedWordArrays can be used to hold bulk data in a more compact way.
    For example:
        Array new:100000 withAll:1
    requires 400k of object memory;

    in contrast,
        SignedWordArray new:100000 withAll:1
    only requires half of it.

SignedWordArrays can be used as literals i.e. you can enter SignedWordArray-constants as: 
    #u16( element1 element2 .... elementN ) 
    #s16( element1 element2 .... elementN ) 
for example:
    #u16(10 127 0x7FFF 0xFFFF)
    #s16(-1 10 -128 127 0x7FFF -0x8000)

Aliased as Int16Array.

[memory requirements:]
    OBJ-HEADER + (size * 2)


[caveat:]
    should probably be renamed to Int16Array
    (there is an alias named 'Int16Array', but when inspected,
    it presents itself as SignedWordArray)

copyright
COPYRIGHT (c) 1997 eXept Software AG
             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:

 elementByteSize

for bit-like containers, return the number of bytes stored per element.
Here, 2 is returned

 literalTokenPrefix

 maxVal

the maximum value which can be stored in instances of me.
For SignedWordArrays, this is 16r7FFF (largest 16bit signed int)

 minVal

the minimum value which can be stored in instances of me.
For SignedWordArrays, this is -16r8000 (smallest 16bit signed int)