Learn Haskell step by step

Enviroment set-up

Article is a little bit outdated. In 2022 I still could archive the same results with some deviations of the installation process. Tip: don't afraid to read error messages :) Setting Up Haskell In Vs Code With Stack And The IDE Engine

Inside ghci

:set prompt "ghci> "

:set +t   -- to print more type information for each entry    
:unset +t    
:type 'a' -- to print type information for a value   

:m +Data.Ratio -- to add rational numbers operations

:load src/Chapter_2/add.hs -- to add source files  
:cd /tmp -- to change directories inside ghci   

:show bindings

:info -- gets ghci to tell us everything it knows about a name

Compiler commands

runghc src/Chapter_1/SimpleProgram < src/Chapter_1/quux.txt

Compile haskell source to an executable named InteractWith. We need -main-is because by default ghc assume that main is located in Main module. This is not our case.

ghc -main-is Chapter_4.InteractWith  src/Chapter_4/InteractWith.hs

TODOs

• you don't need readme for each chapter but good comment sections
• test should not be module? Link
• maybe I should not blindly copy paste from the book, considering copyright
• rename modules. From Chapter to related topic
• you can rethink the whole repo as Haskell+f programming learning hub. Not only Real World Haskel
• put ghci commands in the separate directory and rething this README as a Table of Contents
• add daml directory. you can start with DA.VALIDATION move the idea to another repo
• add circle ci with tests and protect main