Small changes to links and haskell comments

Readme.md

@@ -28,7 +28,7 @@ using functional paradigms.
 ## Files ##
 
 You may download both [the slides PDF][slides] in handout mode, and a
-[source archive][source] of the examples used during the talk.
+[source archive][examples] of the examples used during the talk.
 
 ## Structure ##
 
@@ -51,7 +51,8 @@ Part Three
 ## Pages ##
 
 There are two main-pages for this talk. One is my [homepage][wtfoff], the other
-one is the [GitLab-server of F3L][f3lgit]
+one is the [GitLab-server of F3L][f3lgit] which contains the whole example and
+slide sources.
 
 ## Compiling ##
 
@@ -80,24 +81,42 @@ lualatex -shell-escape wtfunction
 
 ### Examples ###
 
-TBC
+Exmaple 00_dafunc.cpp is not that important, and should build with any decent C++-compiler.
+
+For the haskell-example, use `ghci`, then `:load 01_haskell.hs`. The functions provided are:
+
+ * extract (≅ fst)
+ * addto
+ * mfold (≅ foldl)
+ 
+02_python.py can be executed using `python`, or inspected using `python -m`. It
+provides:
+
+ * a debug-function usable as decorator
+ * a bubblesort-implementation using functional paradigms.
+ 
+03_cpp.cpp needs a compiler capable of C++11. It shows code- and
+runtime-examples for `for_each`, `transform` and `accumulate`.
+
+04_cpp17.cpp needs a compiler capable of C++17-folds, `gcc` or `clang` should
+do. Then compile using the option `std=c++1z`
 
 ## License ##
 
-This is licensed under MIT-License. For the exact text, see License.txt.
+This is licensed under MIT-License. For the exact formulation, see License.txt.
 
+[examples]: https://www.pheerai.de/assets/wtf_examples.tar.gz
 [f3l]: https://www.f3l.de
 [f3lgit]: https://git.f3l.de/pheerai/wtfunctional
 [fira]: https://github.com/mozilla/Fira
 [haskell]: https://www.haskell.org
 [inconsolata-g]: http://leonardo-m.livejournal.com/77079.html
 [lualatex]: http://luatex.org
-[mailto]: mailto://oli_r@fg4f.de
+[mailto]: mailto:oli_r@fg4f.de
 [minted]: http://github.com/gpoore/minted
 [pygments]: http://pygments.org/
 [python]: https://python.org/
-[slides]: ??
-[source]: ??
+[slides]: https://www.pheerai.de/assets/wtf_slides.pdf
 [texlive]: https://www.tug.org/texlive/
 [wtfoff]: https://www.pheerai.de/wtf/
 

examples/01_haskell.hs

@@ -2,25 +2,29 @@ extract :: [a] -> a
 extract [] = error("Too few objects")
 extract (x:xs) = x
 a = extract [1,2,3,4,5]
+-- a == 1
+-- better use fst
 
 addto :: (Num a) => [a] -> a -> [a]
 addto [] _ = [] -- edge case (list empty)
 addto (x:xs) y = (x+y) : addto xs y
 b = [1..4]
--- c == [5,6,7,8]
 c = addto b 4
+-- c == [5,6,7,8]
+-- better use c = map (+4) b
 
 -- d == [25,36,49,64]
 d = map (^2) c
 
--- e == [6,8]
 e = filter (\x -> (mod x 2) == 0) c
+-- e == [6,8]
 
 mfold :: (t -> t1 -> t1) -> t1 -> [t] -> t1
 mfold f z [] = z
 mfold f z (x:xs) = f x (mfold f z xs)
 msum = mfold (+) 0
 g = msum [1..100]
+-- use sum [1..100] instead, and use right folds
 
 pt = [(a,b,c) | a <- [1..15], b <- [1..a], c <- [1..b], a^2 == b^2 + c^2]