On 15.04.2017 01:29, Walter Bright wrote:
On 4/14/2017 3:41 PM, Timon Gehr wrote:
Haskell does not do that. Why do you think it does?
Do what?
Require 100% purity and immutability. (You're underquoting.)
I did not mention Haskell.
...
You said "come about when". Those things "came about" in Haskell.
This is the original monad paper (in an fp context):
homepages.inf.ed.ac.uk/wadler/papers/marktoberdorf/baastad.pdf
(The paper mentions other programming languages in the intro, but it is
easy to discover that this is just a courtesy/a way to establish relevance.)
This is the original FRP paper: http://conal.net/papers/icfp97/
Back in the 80's, like everyone else, I went about creating a GUI user
interface library. I discovered something interesting - what is
orthogonal and consistent to a computer is anything but when dealing
with people. What people view as orthogonal and consistent is a rat's
nest of exceptions in the code to implement it. This is what makes a
user interface library fiendishly difficult to pull off.
...
Would you mind sharing an example?
It was 30 years ago. I don't remember specifics, but I can think of one
- the tab key. It means different things depending on what box you're
in.
Inserting a tab character vs. moving to the next box?
Some more thoughts - is a box in a fixed position, or is it movable?
Is a box user-resizeable or not? Is the size of a box determined by its
content do do you throw up scroll bars? or maybe relay out the contents?
How do fonts affect this? How about screen resolution? Which parts of a
box should be selectable with cut operations and which not? It just goes
on and on.
...
I see. Maybe that is why I dislike using GUIs so much. :)
There's the famous Windows 'start' button which you click on to turn the
computer off. Of course, it is consistent from a programming point of
view, because it starts the shutdown program.
In any case, look at English. It is not remotely consistent, and drives
programmers to fits trying to parse it. But people find it intuitive.
People get used to convoluted behaviours especially when in large
groups. Synthetic languages are a great deal more orthogonal and
consistent, because this is actually useful. I don't buy that aiming for
inconsistencies is a way to make a system more intuitive when the user
didn't have prior exposure to a similar system. Monads being unpopular
has no bearing on whether the proposed feature is intuitive. (It isn't.
There is a lot of precedent for a lack of explicit monads, but none for
the proposal.)
