| About
            Every expression in Haskell has a type that is determined at compile time. All the types composed together by function application have to match up. If they don't, the program will be rejected by the compiler. Types become not only a form of guarantee, but a language for expressing the construction of programs. Every function in Haskell is a function in the mathematical sense (i.e., "pure"). Even side-effecting IO operations are but a description of what to do, produced by pure code. There are no statements or instructions, only expressions that cannot mutate variables (local or global) nor access state like time or random numbers. You don't have to explicitly write out every type in a Haskell program. Types will be inferred by unifying every type bidirectionally. However, you can write out types if you choose, or ask the compiler to write them for you for handy documentation.
             | About
            Nix is a tool that takes a unique approach to package management and system configuration. Learn how to make reproducible, declarative, and reliable systems. Nix builds packages in isolation from each other. This ensures that they are reproducible and don't have undeclared dependencies, so if a package works on one machine, it will also work on another. Nix makes it trivial to share development and build environments for your projects, regardless of what programming languages and tools you’re using. Nix ensures that installing or upgrading one package cannot break other packages. It allows you to roll back to previous versions and ensures that no package is in an inconsistent state during an upgrade. Nix is a purely functional package manager. This means that it treats packages like values in purely functional programming languages such as Haskell, they are built by functions that don’t have side effects, and they never change after they have been built.
             | About
            The core of extensible programming is defining functions. Python allows mandatory and optional arguments, keyword arguments, and even arbitrary argument lists. Whether you're new to programming or an experienced developer, it's easy to learn and use Python. Python can be easy to pick up whether you're a first-time programmer or you're experienced with other languages. The following pages are a useful first step to get on your way to writing programs with Python! The community hosts conferences and meetups to collaborate on code, and much more. Python's documentation will help you along the way, and the mailing lists will keep you in touch. The Python Package Index (PyPI) hosts thousands of third-party modules for Python. Both Python's standard library and the community-contributed modules allow for endless possibilities.
             | About
            Automate your workflow, let Upsource analyze your code and track the progress, while you focus on improvements. Participate in discussions and manage your reviews without leaving the comfort of your IDE. Explore new changes in the browser with IDE-like navigation, reply by email, and never miss an important change. Discuss changes, @mention others, react to comments, and unlock achievements as you discover new features and help your teammates! Easily make Upsource part of your process, integrate it with issue trackers, CI servers, and sync with GitHub. Don’t worry about outgrowing Upsource! No matter how large your team becomes or how many projects you have, Upsource can handle it. Whether you're looking for a code review tool, insight into your projects' history, or a place to collaborate or expand your developer expertise, Upsource has got you covered! 
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| Company InformationHaskell www.haskell.org | Company InformationNixOS Netherlands nixos.org | Company InformationPython Founded: 1991 www.python.org | Company InformationJetBrains Founded: 2000 Czech Republic www.jetbrains.com/upsource/ | |||
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    FastWebHost
            
            
         
            
                
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