That's not how copyright / trademarks work. Try and name your software Photoshop Kids or Photoshop Palette. Adobe's lawyers will rip you a new one quite quickly if you attempt to tell them "it has nothing to do with editing images".
Intellectual property law is complex and trying to sum it up in a sentence or two is going to give people the wrong impression. However, as much as I'm not a lawyer, I will try to help you dispel a few notions.
First, this is a clearly a trademark issue, not a copyright issue. You can't copyright a name. In fact there are many, many, many things that you can't copyright. It often happens that people conflate the 3 main areas of intellectual property law: copyright, trademarks and patents, but it is quite important that you distinguish between them precisely.
WRT to trademarks, having a similar name is not enough to cause a trademark infringement. It also needs to create confusion in the marketplace. In this case, a tutorial on how to make a command line Haskell app and some kind of web service is really unlikely to cause any confusion.
The problem with trademarks is that, unlike copyright, if you have a trademark you have to defend it or lose it. So if you sue someone over a trademark infringement, the other side can say, "Well, they didn't say anything about this other guy doing the same thing even though they knew about it". This can cause you to lose the trademark.
Because of this, many lawyers err on the side of caution and send out spammy "You are infringing on our trademark" notices to everyone. If you send a quick note back saying, "I don't think there is any possibility of confusion in the market place" (such as this situation), the lawyers will often back off -- unless they truly believe that there is a problem.
Clearly your advice of trying to avoid trademark infringement is good advice. In this case, though, here is pretty clearly no infringement, so it's misplaced. In the very unlikely even that a lawyer asks about it, replying back with the response, "There is no chance for confusion in the market place" will likely be enough (Note: this is not legal advice, and I am not a lawyer).
Interesting side track: The World Wrestling Federation (WWF) became World Wrestling Enterprises (WWE) due to a trademark dispute with the World Wildlife Foundation (WWF). You could reasonably think that there is no way of confusion in the market place, but the World Wildlife Foundation showed that people were hesitant to contribute to them because they actually thought that they were associated with the World Wrestling Federation. That is the key issue, not just the similarity in the name.