I had this happen to me once (and only once, I learned my lesson). Our professor gave us a PDF with the problem description and it had a bit of code in it we were to put into our final program. Well, when I copy and pasted it some of the spaces copied as non-ASCII space.
Oh god pasting code from a PDF, that brings me back.
Doesn't your editor handle that? I don't exactly remember but I kinda remember having a button to convert pasted characters to ascii (mostly used for those annoying stylized unicode quotes)
Apparently Atom didn't/doesn't have that feature, at least to automatically display when problematic characters are present. I believe I ended up taking a hex editor to my code to see what was wrong, since it was only a single loop that appeared to stop the compilation.
