Erlang workshop for Drammen Software meetup

1. Erlang workshop
Reidar Sollid
Erlang workshop in Drammen

2. Erlang
• The world is concurrent
• Things in the world don’t share state
• Things communicate through messages
• Things fail
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- Joe Armstrong

3. Presentation Title - Classification
What is Erlang
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• Created and maintained by Ericsson (now open source)
• Functional, single assignment, strict evaluation, dynamic typing
• Actor model, concurrent oriented, fault tolerant, soft-real-time
• Light weight processes that communicate using message passing
(You can have several processes in one OS/Java thread)
• Erlang started life as modified prolog
• Erlang shell, escript and compiled .beam bytecode

4. What problem to solve
Presentation Title - Classification
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5. What is Elixir
1) A Ruby like language for the Erlang VM
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BEAM
2) Seamless Erlang integration: zero-penalty
Erlang function calls (and vice
versa)
3) Meta programming via macros and a
first-class AST (Abstract syntax tree)
4) Polymorphism via protocols inspired by
Clojure

6. Presentation Title - Classification
And this
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7. Shared memory model
Presentation Title - Classification
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Shared
memory
Process
thread
Process
thread
Process
thread

8. Message passing
Presentation Title - Classification
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Process
thread
Process
thread
Process
thread

9. Concurrency and shared memory model
Presentation Title - Classification
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10. Atoms and variables
• An atom is global constant starting with
lower case char
• A variable starts with a capital char and is
called a variable since it can be bound or
unbound. Once the variable is bound it
can never change.
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11. Pattern matching
Presentation Title - Classification
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12. Pattern matching
• Everything in Erlang is pattern matching
• When assigning a variable, that is really
pattern matching
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13. Loops
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14. No while or for loops ?
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15. Tail optimised recursion
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16. Presentation Title - Classification
Lambdas
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17. BIF (Built in Functions)
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18. OTP
(Open Telecom Platform)
1.Mostly used by finance sector, so it just called OTP now
2.Contains a set of behaviours
4.The standard Erlang/OTP behaviours are:
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1.gen_server
1. For implementing the server of a client-server
relation.
2.gen_fsm
1. For implementing finite state machines.
3.gen_event
1. For implementing event handling functionality.
4.supervisor
1. For implementing a supervisor in a supervision tree.

19. Rebar
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20. Rebar
• Rebar is an Erlang build tool that makes it
easy to compile and test Erlang
applications, port drivers and releases.
• Contains templates for OTP development
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21. Learn you some Erlang
http://learnyousomeerlang.com/
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22. Presentation Title - Classification
Stickers ?
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