[Haskell-cafe] Re: Visual Programming Languages

[Keean Schupke]

Hmm, can't resist commenting on this one!

Bayley, Alistair wrote:

>This was odd...
>
>Some cherry-picked quotes from the manifesto:
>  http://alarmingdevelopment.org/index.php?p=5
>
>
> - Visual languages are not the solution: ... common idea is to replace AST
>structures with some form of graphical diagram. ...
>  
>
Agree, point and grunt is much slower than entering commands. Its like 
being stuck in a country where you don't speak the language - all you 
can do is point at things and grunt ('click') and hope they understand you.

> - Programming is not Mathematics
>  
>
Disagree strongly... Bad programming seems to have little to do with 
mathematics, good programming often has the elegance of a well thought 
out proof. Beauty in programming is like beauty in mathematics.

> - Change is natural: There has been much effort expended to remove the
>concept of mutable state from programming, to be replaced by immutable
>values as in mathematics. This is entirely misguided. ... Monads are a
>reductio ad absurdum.  [ Heresy! :-) ]
>  
>
Change is natural, but that has nothing to do with mutable state.

Parallelism will make mutable state less attractive, as will
hardware/software co-design. Isolating changes within a verifiable
sandbox (like the ST/State monads) reduces errors due to unforseen
interactions.

> - Control flow considered harmful:  ... The primary reason for this is to
>permit side-effects to be ordered by the programmer. ... [ This appears to
>contradict the criticism of monads. ]
>  
>
Agree - control flow causes the possible paths (or corner cases) in the
program to increase exponentially. Program correctness verification becomes
much harder with more possible-paths.

    Keean.