<=Exit class: center, middle .xl[ Programming Languages and Ecosystems ] .author[ John Leung 2015 ] --- class: center, middle .xl[ "7 Languages and Ecosystems in 70 minutes" ] --- # Topics 1. Languages 2. Drawbacks 3. Alternatives --- class: center, middle background-image: url(c_logo.svg) --- class: center, middle background-image: url(Ritchie3.jpg) --- # C - developed by Dennis Ritchie 1969 - 1973 at AT&T Bell Labs - general-purpose, imperative, statically typed - constructs that map efficiently to machine instructions - *"The new assembly"* - typical applications: OS, embedded systems - Influenced by: .md[ * Fortran (John Backus, 1957) * ALGOL (Committe of 8, including John Backus, '58, '60, '68) * PL/1 (IBM, *SHARE* Committee, 1964) * B (Ken Thompson and Dennis Ritchie, 1969) ] --- # C Standards - K&R C, 1978 - Brian Kernighan and Dennis Ritchie published *The C Programming Language* in 1978 - the book served for many years as an informal specification of C, aka *K&R C* - large number of extensions - ANSI C, 1983 - large number of extensions led to the necessity of standardization - the *American National Standards Institue* (ANSI) formed a committee in 1983 to standardize C - ANSI C standard adopted by ISO in 1990 --- # C Standards - C99, 1999 - added: .md[ * inline functions * `long long int` and `complex` data types * variable length array, flexible array members * better floating point support * macros of variable arity * `// single line comments` ] - C11, 2011 - added: .md[ * type generic macros * anonymous structures * better Unicode support * atomic operations * multi-threading * bounds-checked functions * better C++ compatibility ] --- class: center, middle background-image: url(Tiobe_index.png) --- class: center, middle background-image: url(erlang.png) --- class: center, middle background-image: url(joe.armstrong.jpg) --- # Erlang - developed by Joe Armstrong, Robert Virding, and Mike Williams in 1986 - general-purpose, concurrent, functional programming language and runtime system - dynamically typed, automatic memory management - originally a proprietary language within Ericsson (*"Er"*), open sourced in 1998 - designed to support distributed, fault-tolerant, soft real-time, highly available, non-stop applications - supports _hot swapping_ (code can be changed without stopping the system) - active, 18.0, 18.1 released in June, Sep 2015 --- # Erlang Processes - main strength in concurrency via light weight processes - Erlang processes are not OS processes nor OS threads - like OS processes, Erlang processes share no state - processes communicate via share-nothing message passing, removing need for explicit locks - processes are very light weight, only 300 words overhead - millions of processes can be created without much degrade in performance --- # Erlang - language for fault tolerant distributed systems - in GPRS, 3G, LTE mobile networks worldwide - Yaws - web server - Riak, CouchDB, SimpleDB - distributed databases - ejabberd - XMPP server powering Facebook Chat - Chef - configuration management tool re-written from Ruby - RabbitMQ - Message Queuing Protocol implementation - RPC proxies to ruby processes for GitHub - WhatsApp, Goldman Sachs HFT programs - Call of Duty, League of Legends, Battlestar Online game servers --- class: center, middle background-image: url(python.svg) --- class: center, middle background-image: url(guido.jpg) --- # Python - developed by Guido van Rossum, released in 1991 - general-purpose, object-oriented, high-level scripting language - design philosophy emphasizes code readability - dynamically typed, automatic memory management - *"The new BASIC"* - *"Batteries Included"* - active, 3.5 released in Sep 2015 - langauge proposals via PEPs (Python Enhancement Proposals) --- # PEP 20 (The Zen of Python) - Beautiful is better than ugly - Explicit is better than implicit - Simple is better than complex - Complex is better than complicated - Readability counts --- # Python Implementations - CPython - official implementation, written in C - PyPy - much faster JIT runtime - Jython, IronPython - JVM, .NET runtimes - Cython - python-like language with cdef type declarations, compiles to C++ - Numba - JIT LLVM compiler via declarator signatures --- # Python - language for Science and Machine Learning - NumPy - matrix library that uses BLAS, allowing matrix calculations to be close to speed other languages using BLAS, even closer if used in PyPy - SciPy, scikit-learn, BioPython, Sage, iPython notebook, Pandas - many deep neural network libraries - best supported language for OpenCV - NLTK - "machine learning" in github: 3337 in python, 2264 in Matlab, 1050 in R, 1006 in Java, 496 in C++ --- class: center, middle background-image: url(lua.svg) --- class: center, middle background-image: url(team.jpg) --- # Lua - created by Roberto Ierusalimschy, Luiz Henrique, Waldemar Celes in 1993 - designed to be a general purpose scripting language with embeddability and extensibilty as primary goals - lightest weight (180kB for full reference interpreter) scripting language - first-class functions, GC, closures, proper tail calls, coroutines - ~50% - 3x faster than python in general benchmarks - dynamically typed, - single data structure: table - simple C API --- # Lua - language for Games, UI, and Embedded Systems - Mods, including Minecraft, Half-Life 2, many others - World of Warcraft UI subsystem - Game Engine for Corona, Moai, and many others - full or large portion of many games - over 40% of Adobe Lightroom is written in Lua - eLua - embedded software applications builder - OpenResty - web server bundling Nginx core --- class: center, middle background-image: url(ruby.svg) --- class: center, middle background-image: url(matz.jpg) --- # Ruby - created by Yukihiro Matsumoto (松本行弘) "Matz", released in 1995 - general purpose, object oriented, dynamically typed scripting language - Why? "Didn't like Perl because it smells like a toy language. Didn't like Python because it's not a true object oriented language. I wanted a genuine object oriented, easy to use scripting language" - Matz 1999 - everything is a true object .sm[ ``` 4.times do |i| puts i end ``` ] --- # Ruby - language for web applications with .giant[ Rails ] .xs[ (and DSLs, web (Github, old Twitter), and other usages where speed isn't critical) ] --- class: center, middle background-image: url(js.jpg) --- class: center, middle background-image: url(eich.jpg) --- # Javascript - developed in 10 days by Brendan Eich in May 1995 - originally called LiveScript, renamed to JavaScript when shipped in Netscape 2.0 in Sep 1995 - designed to be a lightweight interpreted language used in a browser - part of to the ECMA standard in June 1997, but no official "governing" body, hence no official logo - fun fact - *JavaScript* is a trademark of Oracle - predicted by Steve Yegge in 2007 to be *"The Next Big Langauge"* (web2.0 just coined 1+ years ago and ajax just a year ago) - cemented its dominance with introduction of ajax (2005), jQuery (2006), node.js (2009) --- # Javascript - language for web and mobile - *"The new C"*, *"The web assembly"* - now a *"platform"* - languages that compiles to javascript: over 100 - a real platform - WebAssembly (supersedes asm.js) - ports C code without modifications with less than 50% performance hit - web worker - spawn workers that unblocks the UI thread - server application and server with node.js - native mobile applications with Titanium and React native - non-native mobile applications with phonegap and many other frameworks --- class: center, middle background-image: url(coffeescript.jpg) --- class: center, middle background-image: url(jeremy.jpg) --- # CoffeeScript - developed by Jeremy Ashkenas in 2009 - (also creator of Backbone.js and Underscore.js) - syntax heavy borrows from Ruby and Python - most adapted alt-js language --- class: center, middle .xl[ Drawbacks and Alternatives<br>(7 More Languages) ] --- # C Drawbacks - No runtime checking - No strict type checking - No easy object oriented programming support - No exception handling support - Not easy - Solution: C++?, D? --- class: center, middle background-image: url(nim.png) --- class: center, middle background-image: url(Andreas.jpg) --- # [Nim](http://nim-lang.org/) - created by Andreas Rumpf, v0.6 release 2008 - high level, statically typed, imperative language - fast compilation - compiles to C and javascript - supports both automatic and manual memory management - macros, templates, inline, iterators, generators - universal function call syntax - fast GC supporting soft real time systems and pluggable GC module (3 supported) --- # Erlang Drawbacks - Slow for heavy computations - weird syntax - String manipulation --- class: center, middle background-image: url(elixir.png) --- class: center, middle background-image: url(jose.jpg) --- # [Elixir](http://elixir-lang.org/) - created by José Valim in 2012 - functional, concurrent, general purpose language - compiles to bytecode that runs on BEAM - the Erlang VM - same fault tolerant, soft real time, non-stop distributed applications capabilities - can call Erlang functions and vice versa - builtin macros, pattern matching everything is an expression - lazy and async collections with streams - biggest usage in Phoenix Web Framework --- # Python Drawbacks - Still not fast enough for non-matrix computations - Not functional enough - Eg. lambda functions are limited and side effect functions do not return --- # Solutions - PyPy - for speed - [Mochi](https://github.com/i2y/mochi) - for functional programming - Yasushi Itoh, first commit Nov 2014 --- # Lua Drawbacks - indexes start at 1 - both speed and syntax are good, but can still be better --- # Solutions - LuaJIT - for speed - [MoonScript](http://moonscript.org/) - for coffeescript-like syntax - created by Leaf 2011 --- # Ruby Drawbacks - slow --- class: center, middle background-image: url(crystal.jpg) --- # [Crystal](http://crystal-lang.org) - created by Ary Borenszweig, release in 2013 - Statically type-checked but without having to specify the type of variables or method arguments - Compile to efficient native code - able to call C code by writing bindings to it in Crystal - Have compile-time evaluation and generation of code, to avoid boilerplate code - gaining momentum, 3.5k github stars --- # JavaScript Drawbacks - truthy evaluation and type coercion not make much sense - floats and integers have same type Number (64 bits, 53 bits max for integers) - typescript and flowtype for typing --- # [Livescript](http://livescript.net) - derived from coffeescript - adds many features to assist in functional style programming - supports pipes, list comprehension, partial application, function composition - better require of files and functions