<html xmlns:v="urn:schemas-microsoft-com:vml" xmlns:o="urn:schemas-microsoft-com:office:office" xmlns:w="urn:schemas-microsoft-com:office:word" xmlns:m="http://schemas.microsoft.com/office/2004/12/omml" xmlns="http://www.w3.org/TR/REC-html40">
<head>
<meta http-equiv="Content-Type" content="text/html; charset=utf-8">
<meta name="Generator" content="Microsoft Word 15 (filtered medium)">
<style><!--
/* Font Definitions */
@font-face
{font-family:"Cambria Math";
panose-1:2 4 5 3 5 4 6 3 2 4;}
@font-face
{font-family:Calibri;
panose-1:2 15 5 2 2 2 4 3 2 4;}
/* Style Definitions */
p.MsoNormal, li.MsoNormal, div.MsoNormal
{margin:0in;
font-size:11.0pt;
font-family:"Calibri",sans-serif;}
a:link, span.MsoHyperlink
{mso-style-priority:99;
color:blue;
text-decoration:underline;}
span.EmailStyle18
{mso-style-type:personal-reply;
font-family:"Calibri",sans-serif;
color:windowtext;}
.MsoChpDefault
{mso-style-type:export-only;
font-family:"Calibri",sans-serif;}
@page WordSection1
{size:8.5in 11.0in;
margin:1.0in 1.0in 1.0in 1.0in;}
div.WordSection1
{page:WordSection1;}
--></style><!--[if gte mso 9]><xml>
<o:shapedefaults v:ext="edit" spidmax="1026" />
</xml><![endif]--><!--[if gte mso 9]><xml>
<o:shapelayout v:ext="edit">
<o:idmap v:ext="edit" data="1" />
</o:shapelayout></xml><![endif]-->
</head>
<body lang="EN-US" link="blue" vlink="purple" style="word-wrap:break-word">
<div class="WordSection1">
<p class="MsoNormal">Brujo! Yes I read both of these (and your other stuff too) some time back and they have been (and still are) very helpful on my journey. I just watched the presentation earlier today coincidentally in my search and it confirmed most of
what I have learned but still doesn’t tackle my deeper questions like (“am I doing something stupid to even arrive at this line of questioning?” and “why shouldn’t I have a delegate behaviour and/or one of just callbacks?”, etc.).<o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal">Thanks!<o:p></o:p></p>
<p class="MsoNormal">Brett<o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<div style="border:none;border-top:solid #E1E1E1 1.0pt;padding:3.0pt 0in 0in 0in">
<p class="MsoNormal"><b>From:</b> Fernando Benavides <elbrujohalcon@gmail.com> <br>
<b>Sent:</b> Tuesday, August 24, 2021 4:54 PM<br>
<b>To:</b> Brett Hemes <brhemes@mmm.com><br>
<b>Cc:</b> erlang-questions@erlang.org<br>
<b>Subject:</b> [EXTERNAL] Re: Re: I am close to using a behaviour as a pure interface and I feel dirty...<o:p></o:p></p>
</div>
<p class="MsoNormal"><o:p> </o:p></p>
<div>
<p class="MsoNormal">I'm not entirely sure if this will help but a while back I wrote two articles and gave a talk about this subject. But I might have faced it from a different angle.<o:p></o:p></p>
</div>
<div>
<p class="MsoNormal"><o:p> </o:p></p>
</div>
<div>
<p class="MsoNormal">These are the links:<o:p></o:p></p>
</div>
<div>
<p class="MsoNormal">- <a href="https://youtu.be/OWCYD1Q0COQ">https://youtu.be/OWCYD1Q0COQ</a><o:p></o:p></p>
</div>
<div>
<p class="MsoNormal">- <a href="https://medium.com/erlang-battleground/erlang-behaviors-4348e89351ff">
https://medium.com/erlang-battleground/erlang-behaviors-4348e89351ff</a><o:p></o:p></p>
</div>
<div>
<p class="MsoNormal">- <a href="https://medium.com/erlang-battleground/erlang-behaviors-d5bb30d5412b">
https://medium.com/erlang-battleground/erlang-behaviors-d5bb30d5412b</a><o:p></o:p></p>
</div>
<div>
<p class="MsoNormal"><o:p> </o:p></p>
<div>
<div>
<p class="MsoNormal">On Tue, 24 Aug 2021 at 23:47 Brett Hemes <<a href="mailto:brhemes@mmm.com">brhemes@mmm.com</a>> wrote:<o:p></o:p></p>
</div>
<blockquote style="border:none;border-left:solid #CCCCCC 1.0pt;padding:0in 0in 0in 6.0pt;margin-left:4.8pt;margin-right:0in">
<div>
<div>
<p class="MsoNormal" style="mso-margin-top-alt:auto;mso-margin-bottom-alt:auto">> Erlang's behaviour is NOT an interface!<o:p></o:p></p>
<p class="MsoNormal" style="mso-margin-top-alt:auto;mso-margin-bottom-alt:auto">> If you are looking for some analogy from other languages the closest one is abstract classes in C#.<o:p></o:p></p>
<p class="MsoNormal" style="mso-margin-top-alt:auto;mso-margin-bottom-alt:auto"> <o:p></o:p></p>
<p class="MsoNormal" style="mso-margin-top-alt:auto;mso-margin-bottom-alt:auto">This isn’t very helpful... it is the exact same response I find in the forums with no reasoning behind it. I don’t need analogies either; I understand what behaviours are “supposed”
to be from the documentation and comments (perhaps this wasn’t made clear by my post). Where I fall short is “why” are behaviours limited to such and why aren’t more people asking the same questions I am stuck on (regarding polymorphism)? My logic was: yes,
this has been asked and discussed some in the past with no real resolution that I could find... therefore, users must be content/accepting of the tools provided. I am not so naive to think I am the first to need/want such, so there must be a disconnect.<o:p></o:p></p>
<p class="MsoNormal" style="mso-margin-top-alt:auto;mso-margin-bottom-alt:auto"> <o:p></o:p></p>
<p class="MsoNormal" style="mso-margin-top-alt:auto;mso-margin-bottom-alt:auto">I posted my example to motivate my questioning hoping for some insight and/or comfort. As of now, I have proceeded with storing “meta refs” to my child servers that are module/reference
tuples (along with some dangerous and future-maintenance-issue-causing assumptions regarding their “interface”)... and it’s works... it just smells, and I am always eager to learn and find the right/better/best way.<o:p></o:p></p>
<p class="MsoNormal" style="mso-margin-top-alt:auto;mso-margin-bottom-alt:auto"> <o:p></o:p></p>
<p class="MsoNormal" style="mso-margin-top-alt:auto;mso-margin-bottom-alt:auto">Aside: a colleague came across this repo (<a href="https://github.com/eldarko/epolymorph" target="_blank">https://github.com/eldarko/epolymorph</a>) while digging and the readme
seems to capture my use case almost exactly...<o:p></o:p></p>
</div>
</div>
<div>
<div>
<p class="MsoNormal" style="mso-margin-top-alt:auto;mso-margin-bottom-alt:auto"> <o:p></o:p></p>
<p class="MsoNormal" style="mso-margin-top-alt:auto;mso-margin-bottom-alt:auto">Brett<o:p></o:p></p>
</div>
</div>
</blockquote>
</div>
</div>
<p class="MsoNormal">-- <o:p></o:p></p>
<div>
<p class="MsoNormal">Sent from Gmail Mobile by Brujo Benavides<o:p></o:p></p>
</div>
</div>
</body>
</html>