chore(tazjin): Move my presentations to my user directory

Change-Id: I72b25680e7167c3a55477111c28b1d4936c60e2c
Reviewed-on: https://cl.tvl.fyi/c/depot/+/606
Reviewed-by: tazjin <mail@tazj.in>

users/tazjin/presentations/erlang-2016/src/hello.erl

@@ -0,0 +1,5 @@
+-module(hello).
+-export([hello_joe/0]).
+
+hello_joe() ->
+    hello_joe.

users/tazjin/presentations/erlang-2016/src/hello1.erl

@@ -0,0 +1,5 @@
+-module(hello1).
+-export([hello_joe/0]).
+
+hello_joe() ->
+    hello_joe.

users/tazjin/presentations/erlang-2016/src/hello2.erl

@@ -0,0 +1,11 @@
+-module(hello2).
+-export([hello/1]).
+
+hello(Name) ->
+    io:format("Hey ~s!~n", [Name]).
+
+% 3> c(hello2).
+% {ok,hello2}
+% 4> hello2:hello("Joe").
+% Hello Joe!
+% ok

users/tazjin/presentations/erlang-2016/src/hello_server.erl

@@ -0,0 +1,12 @@
+-module(hello_server).
+-export([start_server/0, server/0]).
+
+start_server() ->
+    spawn(fun() -> server() end).
+
+server() ->
+    receive
+        {greet, Name} ->
+            io:format("Hello ~s!~n", [Name]),
+            hello_server:server()
+    end.

users/tazjin/presentations/erlang-2016/src/hello_server2.erl

@@ -0,0 +1,36 @@
+-module(hello_server2).
+-behaviour(gen_server).
+-compile(export_all).
+
+%%% Start callback for supervisor
+start_link() ->
+    gen_server:start_link({local, ?MODULE}, ?MODULE, [], []).
+
+%%% gen_server callbacks
+
+init([]) ->
+    {ok, sets:new()}.
+
+handle_call({greet, Name}, _From, State) ->
+    io:format("Hello ~s!~n", [Name]),
+    NewState = sets:add_element(Name, State),
+    {reply, ok, NewState};
+
+handle_call({bye, Name}, _From, State) ->
+    io:format("Goodbye ~s!~n", [Name]),
+    NewState = sets:del_element(Name, State),
+    {reply, ok, NewState}.
+
+terminate(normal, State) ->
+    [io:format("Goodbye ~s!~n", [Name]) || Name <- State],
+    ok.
+
+%%% Unused gen_server callbacks
+code_change(_OldVsn, State, _Extra) ->
+    {ok, State}.
+
+handle_info(_Info, State) ->
+    {noreply, State}.
+
+handle_cast(_Request, State) ->
+    {noreply, State}.

users/tazjin/presentations/erlang-2016/src/hello_sup.erl

@@ -0,0 +1,24 @@
+-module(hello_sup).
+-behaviour(supervisor).
+-export([start_link/0, init/1]).
+
+%%% Module API
+
+start_link() ->
+    supervisor:start_link({local, ?MODULE}, ?MODULE, []).
+
+%%% Supervisor callbacks
+
+init([]) ->
+    Children = [hello_spec()],
+    {ok, { {one_for_one, 5, 10}, Children}}.
+
+%%% Private
+
+hello_spec() ->
+    #{id       => hello_server2,
+      start    => {hello_server2, start_link, []},
+      restart  => permanent,
+      shutdown => 5000,
+      type     => worker,
+      module   => [hello_server2]}.