How to print formatted Delphi source on a printer?
As suggested, here is my comment as an answer:
To print formatted source code from the Delphi IDE:
Once, when I had to take over a legacy red-headed stepchild project that had always gotten the left over efforts of programmers ordered to work on it, I did a lot of analysis of the code flow and logic using Microsoft Word. I copied the code out of the environment (it was in VB, but the same thing would work in Delphi), pasted it into Word in a mono-spaced type and added comments using text boxes, etc. In the comments, I could condense some obscure sequences into pseudo-code or summarize the requirements and effects of code blocks or do anything else that made the code more understandable to me. There were a few times when I needed to discuss the code with others and at that point I could email or sometimes even print my attempts at making sense from some pretty unruly code.
Although this is a reason why I might print some code, I would probably not do it directly from the IDE.
If you want to do this from your own software, you can use SynEdit.
It highlights code in a TMemo-like component, and you can print that. It's free and doesn't require external dll's or anything.