Brainfuck part

book/SUMMARY.md

@@ -132,6 +132,18 @@
   * [Some interesting facts](languages/haskell/misc.md)
 
   * [Conclusion](languages/haskell/conclusion.md)
+
+* [Brainfuck](languages/haskell/README.md)
+
+  * [Introduction](languages/brainfuck/intro.md)
+
+  * [History](languages/brainfuck/history.md)
+
+  * [Advantages](languages/brainfuck/advantages.md)
+
+  * [Disadvantages](languages/brainfuck/disadvantages.md)
+
+  * [Conclusion](languages/brainfuck/conclusion.md)
 
 ## End
 

book/credits.md

@@ -46,4 +46,9 @@ We have to thank these great people on helping to write this book. Everyone here
 - Lucas Parzianello
 
   - [devRant](https://devrant.com/users/lucaspar)
-  - [GitHub](https://github.com/lucaspar)
+  - [GitHub](https://github.com/lucaspar)
+
+  - Krzysztof Szewczyk
+
+  - [devRant](https://devrant.com/users/KrzysztofSzewczyk)
+  - [GitHub](https://github.com/KrzysztofSzewczyk)

book/languages/brainfuck/README.md

@@ -0,0 +1,6 @@
+# Welcome
+
+> This chapter has been authored by  Krzysztof Szewczyk "Παλαιολόγος".
+
+Welcome to the Brainfuck chapter! I'd like to let you know a bit more about
+this awesome language.

book/languages/brainfuck/advantages.md

@@ -0,0 +1,13 @@
+# Advantages
+
+Generally speaking, currently, Brainfuck is seen as joke language or proof-of-concept language. Therefore, it's not very efficient, nor easy to write.
+
+First of all, it's a really good exercise for your brain! Brainfuck, as the name suggests, is very hard to write and read, but not understand! You don't have to waste a lot of time just to understand this fascinating language, you can view it as Sudoku of programming.
+
+Also, Brainfuck is a great learning tool. You can create code generators, optimizing interpreters, learn JIT & AOT compilation basics, compiler construction (by, for example, creating a compiler from Brainfuck to C or some kind of assembly language to Brainfuck).
+
+Brainfuck is really simple too! It consists of eight instructions so it's really easy to learn.
+
+Let's imagine Brainfuck computer - it would consume a really small amount of power (x86 has wide instruction set, ARM has it tighter, while Brainfuck destroys other real architectures having only eight!) and excel in simple tasks.
+
+Finally, Brainfuck can help to **understand** the basics - how do you multiply two numbers? How do you create a conditional statement? In other languages, it might seem simple, but Brainfuck challenges the programmer creating this unique spirit.

book/languages/brainfuck/conclusion.md

@@ -0,0 +1,15 @@
+# Conclusion
+
+Brainfuck was meant to be a joke language, and it would be reasonable to leave it's as is.
+
+Thinking about Brainfuck in real terms is a bit risky, it's always quicker and easier to program other languages. On the other hand, Brainfuck brings back joy to
+programming allowing you to play around with the smallest units of a computer program while leaving language fully theoretical,
+not binding it to any definite machine (unlike Assembly, allowing you to feel not only joy while programming, but frustration too).
+To program Brainfuck, you'd need just a pencil and a reasonable amount of paper. Of course, you could do the same with other languages,
+but it's way less practical.
+
+To play around with Brainfuck you need basically no experience - basic knowledge of maths and decent imagination are going to be
+sufficient.
+
+Summing around disadvantages and advantages - Brainfuck is impractical and it shouldn't be considered real language. But there's
+nothing bad in playing with it!

book/languages/brainfuck/disadvantages.md

@@ -0,0 +1,11 @@
+# Disadvantages
+
+Let's face it. Brainfuck is esoteric language. It was created as a joke, and conforming to author's will is recommended.
+There are many so-called Brainfuck hackers around, but being honest, You can't earn a living programming in Brainfuck.
+
+Brainfuck is too impractical to be using language in real-world cases. Developers would cost way too much and work really
+inefficiently. Albeit low abstraction level, Brainfuck is memory and CPU time inefficient (a bit like JavaScript on web),
+so it's not very viable to write anything in bare Brainfuck and you'd be better off by using some kind of Brainfuck assembler,
+or HLL to brainfuck compiler, but none of the listed can beat pure C implementation instead of Brainfuck one.
+
+Finally, the language is a bit limited - I/O is limited to console input and output, greatly reducing use cases.

book/languages/brainfuck/history.md

@@ -0,0 +1,12 @@
+# History
+
+Brainfuck was first implemented and described by Urban Müller in 1993, attempting to design a language for which he could write
+the smallest possible compiler. The language was inspired by False. Müller decided to name his language brainfuck
+(with the initial letter in lower case, although it is now often capitalized). He uploaded the first Brainfuck compiler to Aminet
+in 1993. The program came with a readme file, which briefly described the language, and challenged the reader
+ > Who can program anything useful with it? :)
+
+Müller also included an interpreter and some quite elaborate examples
+
+It is not known was Müller aware of or influenced by Böhm's language P'' (1964), of which brainfuck can be considered a minor
+variation.

book/languages/brainfuck/intro.md

@@ -0,0 +1,30 @@
+
+# Introduction
+
+Brainfuck is the most famous esoteric programming language ever made. It's an esoteric language, so it was not meant to be used
+in solving real-world problems (but, no one forbids You too!). The language can't be classified clearly. Partly it's a very high-level language - Brainfuck doesn't bind itself to any architecture making it very portable language. On the other hand, it's very
+low-level language - it supports only addition and subtraction, basic control structure (`while`-like loop), basic I/O (terminal
+only, shrinking capabilities to the absolute minimum), and indefinitely long tape where any byte can be stored arbitrarily. Brainfuck
+is Turing complete, meaning that it is in the same computational class as universal Turing machines. This, plus its amount of
+instructions, makes it a most popular example of a Turing tarpit. This can be proven in many ways, with various restrictions on
+the brainfuck program or interpreter.
+
+Daniel Cristofani wrote universal Turing machine emulator in Brainfuck which is so small we can quote it here:
+
+```bf
++++>++>>>+[>>,[>+++++<[[->]<<]<[>]>]>-[<<+++++>>-[<<---->>-[->]<]]<[<-<[<]+<+[>]<<+>->>>]<]<[<
+]>[-[>++++++<-]>[<+>-]+<<<+++>+>[-[<<+>->-[<<[-]>>-[<<++>+>-[<<-->->>+++<-[<<+>+>>--<-[<<->->-
+[<<++++>+>>+<-[>-<-[<<->->-[<<->>-[<<+++>>>-<-[<<---->>>++<-[<<++>>>+<-[>[-]<-[<<->>>+++<-[<<-
+>>>--<-[<<++++>+>>+<-[<<[-]>->>++<-[<<+++++>+>>--<-[<->>++<[<<->>-]]]]]]]]]]]]]]]]]]]]]]<[->>[
+<<+>>-]<<<[>>>+<<<-]<[>>>+<<<-]]>>]>[-[---[-<]]>]>[+++[<+++++>--]>]+<++[[>+++++<-]<]>>[-.>]
+```
+
+Simulation is one way to prove Turing completeness:
+
+ > If an interpreter for A can be implemented in B, then B can solve at least as many problems as A can.
+
+There are some difficulties with this way of proving Turing completeness (ℒ), but for Brainfuck, it's entirely sufficient. By theory,
+it's ℒ-complete too, so the proof is fully valid.
+
+Brainfuck is an amazing language. One must still understand where it would be suitable, and where it doesn't particularly excel
+at.