AN INTRODUCTION TO ERLANG AND ELIXIR

Wednesday, September 25, 13

WHAT IS ERLANG

Modular, Declarative Language who’s syntax descends from prolog

Wednesday, September 25, 13

WHAT IS ELIXIR

Modular, Declarative language with meta programming facilities whose syntax descends (mostly) from Ruby

Wednesday, September 25, 13

ERLANG VM - WHY SO INTERESTING

Built Around Concurrency

Built in scheduler

Async IO

Concurrent Garbage collector

Wednesday, September 25, 13

ERLANG VM - WHY SO INTERESTING

Small Number of Serializable Types

Pattern Matching

Processes

Process Linking

Immutable Data

Wednesday, September 25, 13

ERLANG VM

Erlang

Elixir

Joxa

LFE

The Concurrent Schemer

Reia

Wednesday, September 25, 13

ERLANG VM - TYPES

Numbers

Atoms

Bit Strings and Binaries

Fun

Tuple

List

Wednesday, September 25, 13

ERLANG VM - FEATURES

Expressions

Functions

Modules

Process

Wednesday, September 25, 13

RECORDS - ERLANG

-module(records).

-record(robot, {name, type=industrial, hobbies, details=[]}).

first_robot() -> #robot{name="Mechatron", type=handmade, details=["Moved by a small man inside"]}.

Wednesday, September 25, 13

RECORDS - ELIXIRdefmodule Records do

defrecord Robots, name: nil, type: industrial, hobbies: nil, details: ["Moved by a small man inside"]

def first_robot do Robot.new(name: "Mechatron", type: :handmade, details: ["Moved by a small man inside"]) endend

Wednesday, September 25, 13

POLYMORPHISM - ELIXIR

defprotocol Blank do

@doc "Returns true if data is considered blank/empty" def blank?(data)end

# Numbers are never blankdefimpl Blank, for: Number do def blank?(_), do: falseend

# Just empty list is blankdefimpl Blank, for: List do def blank?([]), do: true def blank?(_), do: falseend

# Just the atoms false and nil are blankdefimpl Blank, for: Atom do def blank?(false), do: true def blank?(nil), do: true def blank?(_), do: falseend

Wednesday, September 25, 13

METAPROGRAMMING - ELIXIR

defmodule MyMacro do defmacro unless(clause, options) do quote do: if(!unquote(clause), unquote(options)) endend

require MyMacrounless 2 + 2 == 5, do: call_function()

Wednesday, September 25, 13

DOWNSIDES - ERLANG

No Metaprogramming

No Polymorphism (mostly)

Obscure Syntax

Records are horrible

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DOWNSIDES - ELIXIR

Its young, so changes a fair amount

Truthiness is the devil

Macros are not sufficiently flexible (as what I am used to in lisp)

Awkward syntax

Fair amount of inconsistency

Not really accepted by Erlangers

Wednesday, September 25, 13

UPSIDES - ERLANG

Simple, Regular Syntax

Stable - Infrequent Changes

Robust and Extraordinarily well tested

Wednesday, September 25, 13

UPSIDES - ELIXIR

Metaprogramming, Metaprogramming, Metaprogramming

Polymorphism

Non stable (ie, improving) syntax

Robust, usable shell

Did I say metaprogramming

Wednesday, September 25, 13

WRAPPING UP

Rate This Talk - http://speakerrate.com/talks/26081-an-introduction-to-erlang-elixir-eric-merritt

Contact me - @ericbmerritt, ericbmerritt@gmail.com,

Wednesday, September 25, 13