Grapheme clusters, a.k.a.real characters

[Rustom Mody]

On Thursday, July 20, 2017 at 3:21:52 AM UTC+5:30, Rick Johnson wrote:
> On Tuesday, July 18, 2017 at 10:07:41 PM UTC-5, Steve D'Aprano wrote:
> > On Wed, 19 Jul 2017 12:10 am, Rustom Mody wrote:
> 
> [...]
> 
> > > Einstein: If you can't explain something to a six-year-
> > > old, you really don't understand it yourself.
> > >
> >
> > [...]
> >
> > Think about it: it simply is nonsense. If this six year old
> > test was valid, that would imply that all fields of
> > knowledge are capable of being taught to the average six
> > year old. Yeah good luck with that.
> 
> Again, as was the case with your Toupee Fallacy a few days
> ago, you've got it all wrong. The implication of that quote
> was _not_ that six year olds are the "final arbiters of
> truth". LOL. The implication is that explaining anything to
> a six year old is not an easy task. Therefore, a teacher who
> lacks a deep understanding of the subject matter could never
> hope to properly educate a six year old student. 

Nicely stated Rick. [And amused to find myself on the same side!]
In the hope that I am not also on the “Ranting Rick” side here's some thoughts
towards reducing the polemics

For the purposes of this discussion, broadly speaking the knowledge "of 
computers" needs to be classified into 3 categories:

1. Recursive knowledge
2. Specialised pre-existing
3. Standard/Common (sense)/Universal

1. contains most of what would go into a typical CS degree
 - splay/Red-black/AVL trees
 - threads (vs processes)
 - OS, DBMS, compilers/interpreters
 - Big O analysis
 - algorithms, 
 - etc
 - etc

 Algorithms (and all the rest) is “recursive” in the sense that algorithms
 make computers happen/usable/etc; just as computers give meaning to the
 study of algorithms.
 Sure one can take inspiration from guys like Mike Fellows:
  “Computer science is as much about computers as astronomy is about telescopes
   or biology about microscopes”
  And who does a lot of work towards teaching children algorithms without 
  reference to computer technology [http://csunplugged.org/ ]
  But all this is very fringe. In practice 99% of people studying algorithms 
  (and all the rest above) do it in the context of computer (science)

2. Most typical example would be mathematics which predates CS by some millennia

3. is all the zillion things needed to live in civilized society
 - Which side to drive the car on
 - how to read a clock
 - how to turn on the lights (but not stick your finger in the plug)


So coming to the point:
Its not whether Einstein or Mencken¹ is right but rather that  Mencken applies to 
1 whereas Einstein applies to 3

And (IMHO) text should be squarely classed in 3 not 1

The gmas of this world have made shopping lists, written (and taught to write)
letters [my gpa wrote books] long before CS and before any of us existed.

And if suddenly text has moved from being obvious to anyone to something arcane
involving
- codepoints (which are abstract and platonic)
- (≠) glyphs
- (that fit into) octets (whatever that may be except they are not bytes)
- And all other manner of Unicode-gobbledygook 
Something somewhere is wrong


¹ The Mencken quote is as much off as the Einstein one:
https://en.wikiquote.org/wiki/H._L._Mencken