Added images, fixed syntax highlighting

src/css/mk.css

@@ -233,14 +233,14 @@ figure, .figure {
     --b1:   #989EA8;
     --b2:   #E5E8ED;
     --b3:   #F4F7FC;
-    --y:  #A98D50;
+    --y: #A98D50;
-    --o:  #aa6550;
+    --o: #aa6550;
-    --r:     #b85a64;
+    --r: #b85a64;
     --m: #af53b0;
-    --violet:  #846f93;
+    --v: #846f93;
-    --b:    #5679a4;
+    --b: #5679a4;
-    --cyan:    #4c8493;
+    --c: #4c8493;
-    --g:   #728b5c;
+    --g: #728b5c;
 
     /* Solaryzed accented colors */
     --bg: var(--b03);
@@ -438,7 +438,7 @@ blockquote:after, .main blockquote:after {
 }
 
 .org-rainbow-delimiters-depth-2, .org-nix-builtin, .org-variable-name,
-.org-function-name, .org-diff-changed {
+.org-haskell-definition, .org-haskell-operator, .org-function-name, .org-diff-changed {
     color:var(--b);
 }
 
@@ -453,11 +453,11 @@ blockquote:after, .main blockquote:after {
 .org-rainbow-delimiters-depth-5, .org-diff-removed, .TODO {
     color:var(--r);
 }
-.org-rainbow-delimiters-depth-6  {
+.org-rainbow-delimiters-depth-6, .org-haskell-constructor  {
     color:var(--o);
 }
 .org-rainbow-delimiters-depth-7, .org-type, .org-constant, .org-diff-header,
-.IN_PROGRESS {
+.org-haskell-keyword, .org-haskell-type, .IN_PROGRESS {
     color:var(--y);
 }
 .org-rainbow-delimiters-depth-8, .org-sh-heredoc, .org-diff-added, .org-string,
@@ -472,6 +472,7 @@ blockquote:after, .main blockquote:after {
     color:var(--fg2);
 }
 
-.org-highlight-number-number {
+.org-highlight-numbers-number, .org-highlight-number-number
+ {
     color:var(--rfg);
 }

src/posts/0010-Haskell-Now/index.org

@@ -1,33 +1,29 @@
 #+title: Learn Haskell Fast and Hard
 #+subtitle: Blow your mind with Haskell
-#+date: [2012-02-08]
+#+date: [2019-12-15 Sun]
 #+author: Yann Esposito
 #+EMAIL: yann@esposito.host
 #+keywords: Haskell, programming, functional, tutorial                                |
-#+DESCRIPTION: Meta article about how I generate this blog.
+#+DESCRIPTION: Haskell programming tutorial update
 #+OPTIONS: auto-id:t toc:t
 
 #+begin_notes
-A very short and dense tutorial for learning Haskell.
+A very short and intense introduction to Haskell.
+
+This is an update of my old (2012) article.
+A lot of things have changed since then.
+And I took the time to read it again.
 #+end_notes
 
-Thanks to:
+#+begin_quote
+*Prelude*
 
-- [[https://plus.google.com/u/0/113751420744109290534][Oleg Taykalo]]
+In 2012, I really believed that every developer should learn Haskell.
-  you can find a Russian translation here:
+It is the end of 2019 and I still believe it.
-  [[http://habrahabr.ru/post/152889/][Part 1]] /&/
+I don't think everyone needs to be a super Haskell ninja, but they should
-  [[http://habrahabr.ru/post/153383/][Part 2]],
+at least discover what Haskell has to offer.
-- [[http://silly-bytes.blogspot.fr][Daniel Campoverde]] for the Spanish
+Learning Haskell opens your mind.
-  translation here:
+#+end_quote
-  [[http://silly-bytes.blogspot.fr/2016/06/aprende-haskell-rapido-y-dificil_29.html][Aprende
-  Haskell rápido y difícil]],
-- [[http://github.com/joom][Joomy Korkut]] for the Turkish translation
-  here: [[https://github.com/joom/zor-yoldan-haskell][Zor Yoldan
-  Haskell]].
-
-I really believe all developers should learn Haskell. I don't think
-everyone needs to be super Haskell ninjas, but they should at least
-discover what Haskell has to offer. Learning Haskell opens your mind.
 
 Mainstream languages share the same foundations:
 
@@ -36,27 +32,32 @@ Mainstream languages share the same foundations:
 - pointers[fn:1]
 - data structures, objects and classes (for most)
 
-Haskell is very different. The language uses a lot of concepts I had
+Haskell is very different.
-never heard about before. Many of those concepts will help you become a
+The language uses a lot of concepts I had never heard about before.
-better programmer.
+Many of those concepts will help you become a better programmer.
 
-But learning Haskell can be hard. It was for me. In this article I try
+But learning Haskell can be hard.
-to provide what I lacked during my learning.
+It was for me.
+In this article I try to provide as much help as possible to accelerate
+your learning.
 
-This article will certainly be hard to follow. This is on purpose. There
+This article will certainly be hard to follow.
-is no shortcut to learning Haskell. It is hard and challenging. But I
+This is on purpose.
-believe this is a good thing. It is because it is hard that Haskell is
+There is no shortcut to learning Haskell.
-interesting.
+It is hard and challenging.
+But I believe this is a good thing.
+It is because it is hard that Haskell is interesting and rewarding.
 
-The conventional method to learning Haskell is to read two books. First
+Today, I could not really provide a conventional path to learn Haskell.
-[[http://learnyouahaskell.com]["Learn You a Haskell"]] and just after
+So I think the best I can do is point you to the [[https://www.haskell.org/documentation/][haskell.org]] documentation
-[[http://www.realworldhaskell.org]["Real World Haskell"]]. I also
+website.
-believe this is the right way to go. But to learn what Haskell is all
+And you will see that most path involve a quite long learning process.
-about, you'll have to read them in detail.
+By that, I mean that you should read a long book and invest a lot of hours
+and certainly days before having a good idea about what Haskell is all about.
 
 In contrast, this article is a very brief and dense overview of all
-major aspects of Haskell. I also added some information I lacked while I
+major aspects of Haskell.
-learned Haskell.
+I also added some information I lacked while I learned Haskell.
 
 The article contains five parts:
 
@@ -80,20 +81,6 @@ The article contains five parts:
   - More on infinite tree; a more math oriented discussion about
     infinite trees
 
-#+BEGIN_QUOTE
-  Note: Each time you see a separator with a filename ending in =.lhs=
-  you can click the filename to get this file. If you save the file as
- =filename.lhs=, you can run it with
-
-  #+BEGIN_SRC
-    runhaskell filename.lhs
-  #+END_SRC
-
-  Some might not work, but most will. You should see a link just below.
-#+END_QUOTE
-
------
-
 * Introduction
 :PROPERTIES:
 :CUSTOM_ID: introduction
@@ -104,7 +91,8 @@ The article contains five parts:
 :CUSTOM_ID: install
 :END:
 
-blogimage("Haskell-logo.png", "Haskell logo")
+#+CAPTION: Haskell logo
+[[./Haskell-logo.png]]
 
 There are different way to install Haskell, I would recommend to use
 [[https://haskellstack.org][=stack=]].
@@ -124,7 +112,8 @@ Tools:
 :CUSTOM_ID: don't-be-afraid
 :END:
 
-blogimage("munch_TheScream.jpg","The Scream")
+#+CAPTION: The Scream
+[[./munch_TheScream.jpg]]
 
 Many books/articles about Haskell start by introducing some esoteric
 formula (quick sort, Fibonacci, etc...). I will do the exact opposite.
@@ -217,7 +206,8 @@ languages.
 :CUSTOM_ID: very-basic-haskell
 :END:
 
-blogimage("picasso_owl.jpg","Picasso minimal owl")
+#+CAPTION: Picasso minimal owl
+[[./picasso_owl.jpg]]
 
 Before continuing you need to be warned about some essential properties
 of Haskell.
@@ -521,7 +511,8 @@ really watch this great (and funny) video:
 :CUSTOM_ID: essential-haskell
 :END:
 
-blogimage("kandinsky_gugg.jpg","Kandinsky Gugg")
+#+CAPTION: Kandinsky Gugg
+[[./kandinsky_gugg.jpg]]
 
 I suggest that you skim this part. Think of it as a reference. Haskell
 has a lot of features. A lot of information is missing here. Come back
@@ -769,7 +760,8 @@ The hard part can now begin.
 :CUSTOM_ID: functional-style
 :END:
 
-blogimage("hr_giger_biomechanicallandscape_500.jpg","Biomechanical Landscape by H.R. Giger")
+#+CAPTION: Biomechanical Landscape by H.R. Giger
+[[./hr_giger_biomechanicallandscape_500.jpg]]
 
 In this section, I will give a short example of the impressive
 refactoring ability provided by Haskell. We will select a problem and
@@ -1056,7 +1048,8 @@ We use this method to remove the =l=:
 :CUSTOM_ID: higher-order-functions
 :END:
 
-blogimage("escher_polygon.png","Escher")
+#+CAPTION: Escher
+[[./escher_polygon.png]]
 
 To make things even better we should use higher order functions. What
 are these beasts? Higher order functions are functions taking functions
@@ -1286,7 +1279,8 @@ another essential aspect of Haskell: /Types/.
 :CUSTOM_ID: types
 :END:
 
-blogimage("salvador-dali-the-madonna-of-port-lligat.jpg","Dali, the madonna of port Lligat")
+#+CAPTION: Dali, the madonna of port Lligat
+[[./salvador-dali-the-madonna-of-port-lligat.jpg]]
 
 #+BEGIN_QUOTE
   %tldr
@@ -1405,6 +1399,9 @@ errors are caught before run time. Generally, in Haskell:
 -----
 
 *** Type construction
+:PROPERTIES:
+:CUSTOM_ID: type-construction
+:END:
 
 You can construct your own types. First, you can use aliases or type
 synonyms.
@@ -1565,7 +1562,8 @@ This prints:
 :CUSTOM_ID: trees
 :END:
 
-blogimage("magritte-l-arbre.jpg","Magritte, l'Arbre")
+#+CAPTION: Magritte, l'Arbre
+[[./magritte-l-arbre.jpg]]
 
 We'll just give another standard example: binary trees.
 
@@ -1761,7 +1759,8 @@ Binary tree of Char binary trees:
 This is why I chose to prefix each line of tree display by =:= (except
 for the root).
 
-blogimage("yo_dawg_tree.jpg","Yo Dawg Tree")
+#+CAPTION: Yo Dawg Tree
+[[./yo_dawg_tree.jpg]]
 
 #+BEGIN_SRC haskell
   putStrLn "\nTree of Binary trees of Char binary trees:"
@@ -1826,7 +1825,8 @@ a tree containing a tree of trees!
 :CUSTOM_ID: infinite-structures
 :END:
 
-blogimage("escher_infinite_lizards.jpg","Escher")
+#+CAPTION: Escher
+[[./escher_infinite_lizards.jpg]]
 
 It is often said that Haskell is /lazy/.
 
@@ -2064,7 +2064,8 @@ rewarding.
 :CUSTOM_ID: deal-with-io
 :END:
 
-blogimage("magritte_carte_blanche.jpg","Magritte, Carte blanche")
+#+CAPTION: Magritte, Carte blanche
+[[./magritte_carte_blanche.jpg]]
 
 #+BEGIN_QUOTE
   %tldr
@@ -2331,7 +2332,8 @@ If you practice a bit, you should be able to /use/ =IO=.
 :CUSTOM_ID: io-trick-explained
 :END:
 
-blogimage("magritte_pipe.jpg","Magritte, ceci n'est pas une pipe")
+#+CAPTION: Magritte, ceci n'est pas une pipe
+[[./magritte_pipe.jpg]]
 
 #+BEGIN_QUOTE
   Here is a %tldr for this section.
@@ -2553,20 +2555,21 @@ With, of course: =actionN w :: (World) -> (a,World)=.
 #+BEGIN_QUOTE
   IMPORTANT: there are only two important patterns to consider:
 
-  #+BEGIN_EXAMPLE
+  #+BEGIN_SRC haskell
-      let (x,w1) = action1 w0 in
+    let (x,w1) = action1 w0 in
-      let (y,w2) = action2 x w1 in
+    let (y,w2) = action2 x w1 in
-  #+END_EXAMPLE
+  #+END_SRC
 
   and
 
-  #+BEGIN_EXAMPLE
+  #+BEGIN_SRC haskell
-      let (_,w1) = action1 w0 in
+    let (_,w1) = action1 w0 in
-      let (y,w2) = action2 w1 in
+    let (y,w2) = action2 w1 in
-  #+END_EXAMPLE
+  #+END_SRC
 #+END_QUOTE
 
-leftblogimage("jocker_pencil_trick.jpg","Jocker pencil trick")
+#+CAPTION: Jocker pencil trick
+[[./jocker_pencil_trick.jpg]]
 
 Now, we will do a magic trick. We will make the temporary world symbols
 "disappear". We will =bind= the two lines. Let's define the =bind=
@@ -2805,12 +2808,13 @@ Imagine what it would look like without the =(>>)= and =(>>=)=.
 :END:
 
 #+begin_comment
-blogimage("dali_reve.jpg","Dali, reve. It represents a weapon out of the
+#+CAPTION: Dali, reve. It represents a weapon out of the
 mouth of a tiger, itself out of the mouth of another tiger, itself out
 of the mouth of a fish itself out of a grenade. I could have choosen a
 picture of the Human centipede as it is a very good representation of
 what a monad really is. But just to think about it, I find this
-disgusting and that wasn't the purpose of this document.")
+disgusting and that wasn't the purpose of this document.
+[[./dali_reve.jpg]]
 #+end_comment
 
 Now the secret can be revealed: =IO= is a /monad/. Being a monad means
@@ -3002,7 +3006,8 @@ lists.
 :CUSTOM_ID: the-list-monad
 :END:
 
-blogimage("golconde.jpg","Golconde de Magritte")
+#+CAPTION: Golconde de Magritte
+[[./golconde.jpg]]
 
 The list monad helps us to simulate non-deterministic computations. Here
 we go: