[Tutor] Re: [Edu-sig] Off topic musings

Dethe Elza delza@alliances.org
Mon, 20 Aug 2001 11:00:04 -0700

For the OSI-like model you might want to break it up a bit further:

1 / Physical - bits and bytes defined by machine architecture.

2 / Machine-specific - this is the actual instruction set for a given 

3 / Implementation - this includes data primitives of the given language.

4 / Implementation Groupings - collections, arrays, lists and structured 
types which are built into the language.

5 / Application - Developer-defined data types and tie-ins with other 
systems (RDBMS, etc).

6 / Extensions - Plugins or enhancements which are not part of the 
original program, but operate within it's context and add additional 
information structure. (Would XML go here?)

7 / User-defined - Some programs allow the user to extend the data set 
(by embedding Python, say).

Hmmm.  I probably should have numbered from zero, my bad %-)


1/ Physical - bits/bytes, defined by the machine architecture
            operations are CPU specific, include bitwise OR/AND/NOT 
        and binary arithmetic...

2/ Implementation/Environment - data types defined by the programming 
         environment - object in Smallktalk; int, float, char in C 
      etc...           Operations include built in operators for arithmetic,
           boolean logic and I/O.

[Question: Where do collections: arrays, lists etc fit into the 
    layer proposal?]

3/ Application - User defined data types - records, files, 
RDBMS Tables etc
           Operations are user defined functions/procedures etc.

(Alan, sorry about the duplicate, I keep forgetting that reply doesn't 
go to the group on this list).


Dethe Elza (delza@burningtiger.com)
Chief Mad Scientist
Burning Tiger Technologies (http://burningtiger.com)


Dethe Elza (delza@burningtiger.com)
Chief Mad Scientist
Burning Tiger Technologies (http://burningtiger.com)