Re: base

[Eli Zaretskii <eliz@gnu.org>]

> From: Óscar Fuentes <ofv@wanadoo.es>
> Date: Wed, 25 Aug 2010 15:13:41 +0200
> 
> The teachable mental model was something you insistently asked for on
> the first weeks of the transition to bzr.

I may be misremembering, but I think I was asking something entirely
different.

> It is like the Principles of Physics that, once mastered, are
> extremely useful while working with everything else on the field.

Careful! I majored in Physics.

> Git has simple foundations and those are explained on several places
> on the net. See for example
> 
> http://www.newartisans.com/blog_files/git.from.bottom.up.php

Once again, this is internals, not something users should need to
grasp to use the tool effectively.  We use dozens of programs every
day without any comparable knowledge of how they work and what are the
data structures they manipulate.  Take any example you like: Make,
GCC, GDB, you name it.  Unless you happened to hack them at some
point, the "mental model" each of us has about these tools generally
has nothing to do with the data structures and algorithms you will
find if you study the code.

IOW, a "mental model" is rules of the game, they have nothing to do
with the under the hood machinery that actually makes the game tick.

> There is no such thing for bzr. There was some failed attempt of writing
> an equivalent document, which tells lots about the "simplicity" of bzr.

I rather think it speaks volumes about the (in)ability of Bazaar
developers to write good documentation.  The user guide reads like it
was written by someone whose first language is not English and who
cannot explain herself in _any_ language.

> Git is a simple model wrapped on a complex UI. Bzr is a complex model
> wrapped on a deceptively simple UI. Changing the UI is easy (and there
> are lots for git.) Changing the underlying model is almost impossible.

I have no idea what is the underlying model in Bazaar, and I don't
really care how complex it is, as long as its UI is simple enough for
me to build my own mental model.  And as long as the UI is simple
enough, I see no reason to change the underlying model.

I can also tell you that after spending a year studying the display
engine of Emacs, I think nothing can ever seem complex to me ;-).
What I did learn during this year is that complex models are not
necessarily bad or ugly or not extensible: look what I was able to do
with the display engine without changing anything in its basic
architecture and design.