On Feb 10, 2005, at 6:50 AM, Henning Thielemann wrote:
On Thu, 10 Feb 2005, [ISO-8859-1] Thomas Jäger wrote:
Altogether, the spirit of the page seems to be "use as little syntactic sugar as possible" which maybe appropriate if it is aimed at newbies, who often overuse syntactic sugar (do-notation).
This overuse is what I observed and what I like to reduce. There are many people advocating Haskell just because of the sugar, which let interested people fail to see what's essential for Haskell. When someone says to me that there is a new language which I should know of because it supports definition of infix operators and list comprehension, I shake my head and wonder why he don't simply stick to Perl, Python, C++ or whatever.
If you're trying to avoid obscurity, why advocate point-free style? I ask this question to be deliberately provocative; I'm not trying to single you out in particular. So, to everybody: What's so great about point-free style? Is it really clear or obvious what
map . (+)
means? Contrast this with
\n -> map (+n)
or
\n xs -> map (+n) xs
I submit that, while it is possible to develop a reading knowledge of point-free style, non-trivial use of point-free computations---compositions of functions with arity greater than 1, as above, compositions of sections of composition or application, arrow notation without the sugar, and so forth---will always be more difficult to read and understand than the direct version. I submit that this is true even if one is familiar with point-free programming and skilled in its use. Even something as simple as eta-reduction (as in the second and third functions above) can seriously obscure the meaning of program code by concealing the natural arity of a function. -Jan-Willem Maessen