<div dir="auto">Hi Jeroen,</div><div dir="auto">I just tried it on mac with the latest Cuis and I get the same results as you. However, using MD5NonPrimitive instead of MD5 I get the correct result (note that you will get a message not understood exception, because it sends the message #doWithIndex: that doesn’t exist, you just need to replace it with #withIndexDo:).</div><div dir="auto"> </div><div> <div class="gmail_quote gmail_quote_container"><div dir="ltr" class="gmail_attr">On Sun, Nov 9, 2025 at 05:53 Jeroen Kouwer via Cuis-dev <<a href="mailto:cuis-dev@lists.cuis.st">cuis-dev@lists.cuis.st</a>> wrote: </div><blockquote class="gmail_quote" style="margin:0px 0px 0px 0.8ex;border-left-width:1px;border-left-style:solid;padding-left:1ex;border-left-color:rgb(204,204,204)">Hello, I'm new to this list and new to Smalltalk development. I'm a software engineer by profession and grew up with Unix (SVR4), Pascal and C. Since then I've moved to Linux, Java and C++ and although I've read about Smaltalk and I have been intrigued with the idea behind it, I've never actually programmed in it. Until now. I've started The Cuis Book, together with the SBE and the Cuis Cook Book, and am currently trying to solve the first year of the Advent of Code (2015) in Smalltalk (the Cuis version [1]). The first three days went really well. The challenge came on day four: having to use MD5 hash calculation. Cuis, out of the box, doesn't come with an MD5 class. A little searching led me to the Cryptography package [2] and I installed the package using the File List. Side note: This package does not define a feature, so when next starting the image (provided having saved it) it throws you into the debugger. The package is recognized, but when checking for new versions it finds out that there's no feature defined (nil is not a valid feature) and this part of opening the image cannot handle that: ``` UndefinedObject(Object)>>doesNotUnderstand: #isLaterThan: [] in ChangeSet class>>installNewUpdates: ... ``` However, this can be solved by saving the package (open Installed Packeges); saving the package apparently adds the category as feature to the *.<a href="http://pck.st" rel="noreferrer" target="_blank">pck.st</a>. Back to Cryptography and feature Cuis-System-Hashing (from the Cryptography package [2]): I cannot get the MD5 class to behave as I expect it to behave. I expect that each call to hashMessage with the same message results in the same hash, which it does in Squeak and Pharo (after some frustration I did some checking). After having loaded the package for the first time and executing it the results are as expected: ``` ((MD5 new) hashMessage: 'abcdef609043') hex. '000001DBBFA3A5C83A2D506429C7B00E' . ``` Executing it a second time results in: ``` ((MD5 new) hashMessage: 'abcdef609043') hex. 'D1CE4AB38D6D9DC0E1FF789725EFA294' . ``` Each consecutive execution results in a different value, which is not what I expected! (I've managed to solve day four by resorting to Squeak :o, sorry...) Does anyone has an idea why this calculation keeps on producing new values on each execution? Regards, Jeroen Kouwer P.S. I have observed the same behavior with Cuis 7.2 [3] [1] <a href="https://github.com/Cuis-Smalltalk/Cuis-Smalltalk-Dev" rel="noreferrer" target="_blank">https://github.com/Cuis-Smalltalk/Cuis-Smalltalk-Dev</a> [2] <a href="https://github.com/garduino/Cuis-Smalltalk-Cryptography" rel="noreferrer" target="_blank">https://github.com/garduino/Cuis-Smalltalk-Cryptography</a> [3] <a href="https://github.com/Cuis-Smalltalk/Cuis7-2" rel="noreferrer" target="_blank">https://github.com/Cuis-Smalltalk/Cuis7-2</a> -- Cuis-dev mailing list <a href="mailto:Cuis-dev@lists.cuis.st" target="_blank">Cuis-dev@lists.cuis.st</a> <a href="https://lists.cuis.st/mailman/listinfo/cuis-dev" rel="noreferrer" target="_blank">https://lists.cuis.st/mailman/listinfo/cuis-dev</a> </blockquote></div></div>