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%% File: person.hrl |
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|
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%%----------------------------------------------------------- |
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%% Data Type: person |
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%% where: |
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%% name: A string (default is undefined). |
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%% age: An integer (default is undefined). |
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%% phone: A list of integers (default is []). |
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%% dict: A dictionary containing various information |
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%% about the person. |
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%% A {Key, Value} list (default is the empty list). |
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%%------------------------------------------------------------ |
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-record(person, {name, age, phone = [], dict = []}). |
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|
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-module(person). |
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-include("person.hrl"). |
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-compile(export_all). % For test purposes only. |
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|
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%% This creates an instance of a person. |
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%% Note: The phone number is not supplied so the |
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%% default value [] will be used. |
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|
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make_hacker_without_phone(Name, Age) -> |
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#person{name = Name, age = Age, |
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dict = [{computer_knowledge, excellent}, |
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{drinks, coke}]}. |
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|
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%% This demonstrates matching in arguments |
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|
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print(#person{name = Name, age = Age, |
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phone = Phone, dict = Dict}) -> |
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io:format("Name: ~s, Age: ~w, Phone: ~w ~n" |
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"Dictionary: ~w.~n", [Name, Age, Phone, Dict]). |
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|
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%% Demonstrates type testing, selector, updating. |
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|
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birthday(P) when is_record(P, person) -> |
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P#person{age = P#person.age + 1}. |
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|
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register_two_hackers() -> |
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Hacker1 = make_hacker_without_phone("Joe", 29), |
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OldHacker = birthday(Hacker1), |
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% The central_register_server should have |
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% an interface function for this. |
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central_register_server ! {register_person, Hacker1}, |
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central_register_server ! {register_person, |
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OldHacker#person{name = "Robert", |
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phone = [0,8,3,2,4,5,3,1]}}. |
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|
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%% From https://erlang.org/doc/programming_examples/records.html#a-longer-example |
